article_text
stringlengths 294
32.8k
⌀ | topic
stringlengths 3
42
|
|---|---|
Earth's surface teems with quartz. But on a giant world 1,300 light-years away, quartz zips through the planet's clouds.
Scientists pointed the James Webb Space Telescope — the most powerful observatory in space — at planet WASP-17 b, a gas giant world with temperatures of some 2,700 degrees Fahrenheit (1,500 degrees Celsius). For the first time, the researchers found evidence of tiny particles made of pure quartz in the atmosphere.
"We were thrilled!" David Grant, a scientist at the University of Bristol who worked on the research, said in a statement.
In the study, published in the peer-reviewed science journal Astrophysical Journal Letters, astronomers used a clever strategy to look into WASP-17 b's extremely distant clouds. They waited as the gas giant passed in front of its star, and then used an instrument aboard the Webb telescope (a spectrograph) to capture the light passing through the atmosphere. Similar to separating light into a rainbow of colors using a prism, the spectrograph allowed the research team to see what elements or minerals were present, and which ones weren't. This method, called "transmission spectroscopy," is one of the few ways we can glimpse the makeup of alien atmospheres in distant realms of the Milky Way Galaxy.
"We were thrilled!"
These quartz (silicon and oxygen) particles are likely to be incredibly small — on the order of one-millionth of one centimeter — but are "probably similar in shape to the pointy hexagonal prisms found in geodes and gem shops on Earth," NASA explains. Unlike on Earth, this quartz might be forged in the scorching atmosphere, as opposed to on the surface.
Peering into planets like WASP-17 b allows astronomers to better grasp and catalogue what other planets and solar systems are made of, and whether some might even contain environs suitable for life. (A "hot Jupiter" like WASP-17 b is not a candidate for life to develop.)
The Webb telescope's powerful abilities
The Webb telescope — a scientific collaboration between NASA, the ESA, and the Canadian Space Agency — is designed to peer into the deepest cosmos and reveal new insights about the early universe. But it's also peering at intriguing planets in our galaxy, along with the planets and moons in our solar system.
Want more science and tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newsletter today.
Here's how Webb is achieving unparalleled feats, and likely will for decades:
- Giant mirror: Webb's mirror, which captures light, is over 21 feet across. That's over two and a half times larger than the Hubble Space Telescope's mirror. Capturing more light allows Webb to see more distant, ancient objects. As described above, the telescope is peering at stars and galaxies that formed over 13 billion years ago, just a few hundred million years after the Big Bang.
"We're going to see the very first stars and galaxies that ever formed," Jean Creighton, an astronomer and the director of the Manfred Olson Planetarium at the University of Wisconsin–Milwaukee, told Mashable in 2021.
- Infrared view: Unlike Hubble, which largely views light that's visible to us, Webb is primarily an infrared telescope, meaning it views light in the infrared spectrum. This allows us to see far more of the universe. Infrared has longer wavelengths than visible light, so the light waves more efficiently slip through cosmic clouds; the light doesn't as often collide with and get scattered by these densely packed particles. Ultimately, Webb's infrared eyesight can penetrate places Hubble can't.
"It lifts the veil," said Creighton.
- Peering into distant exoplanets: The Webb telescope carries specialized equipment called spectrographs that will revolutionize our understanding of these far-off worlds. The instruments can decipher what molecules (such as water, carbon dioxide, and methane) exist in the atmospheres of distant exoplanets — be they gas giants or smaller rocky worlds. Webb will look at exoplanets in the Milky Way galaxy. Who knows what we'll find?
"We might learn things we never thought about," Mercedes López-Morales, an exoplanet researcher and astrophysicist at the Center for Astrophysics-Harvard & Smithsonian, told Mashable in 2021.
Already, astronomers have successfully found intriguing chemical reactions on a planet 700 light-years away, and as described above, the observatory has started looking at one of the most anticipated places in the cosmos: the rocky, Earth-sized planets of the TRAPPIST solar system.
Topics NASA | Chemistry and Material Sciences |
NASA’s Parker Solar Probe has just smashed through the record for the fastest object ever created by humankind. The probe was the previous holder of the record. The new record, which measures 635,266 kilometers (394,736 miles) per hour, happened during the probe’s most recent approach to the Sun.
The previous record accomplished by the probe was 586,863.4 kilometers (346,600 miles) per hour, and it was set just three years ago. Just for a little more clarification of how fast this is, an aircraft traveling at these speeds could circumnavigate our planet 15 times in one hour. Those speeds are insane on their own, but Parker isn’t done yet.
The probe is just now on its 17th loop, with another seven laps set to happen before it spirals headfirst into the Sun’s surface. It didn’t just set the record for the fastest object ever created by humankind, either — it also set a new record for the closest proximity to the Sun at just 7.26 million kilometers, making it a close flyby of our star.
To accomplish these speeds and the laps that Parker is currently following, NASA scientists had to calculate an exact path that would see the probe lining up with Venus just enough to slow the probe as it continued its orbit, slowly closing the rings of its orbit until it crashes into the Sun.
It is no small feat by any means, and seeing the successes that Parker has ushered in, including being the first NASA spacecraft to touch the Sun, has been an amazing thing to see as an avid follower of what NASA is doing to learn more about our solar system.
The Parker Solar Probe has just set a new record for the fastest object created by humankind, and it will one day turn to melted metal as it crashes into the Sun after 24 orbits around our star, gleaming as much information from the star as it can in the meantime. | Chemistry and Material Sciences |
The planet Mercury may be hot, but it appears to be cooling down. That's the conclusion of a new study that looked for the kinds of features on Mercury that can form as the surfaces of planets contract due to cooling. These vertical faults, called "graben," are not only common across the planet's surface but appear to have formed within the last few hundred million years—and possibly much more recently.
All of which suggests that the stresses caused by a cooling planet are still playing out on the Solar System's smallest non-dwarf planet.
Crunch time
The process of building a planet necessarily generates a lot of heat as impactors of various sizes deliver both matter and energy to the growing planet. The radioactive elements they deliver can also heat the planet's interior. For the rocky planets of our Solar System, this heat means a differentiated interior, with layers of lighter rocks on top of a liquid core.
Over time, however, that heat escapes to space, allowing the interior of planets to gradually cool. Since smaller planets have less hot material compared to their surface area, this cooling happens most quickly on Mars and Mercury.
The cooling can have significant impacts on the planet. Once things cool sufficiently, it means an end to liquid cores and the loss of any magnetic fields generated through their rotation. As the rocks above the core cool, they also solidify, shutting down processes like volcanism and the plate tectonics seen on Earth.
That doesn't mean the end of all tectonic activity, though, as the cooling itself can generate other stresses that can reshape the surface of planets. Most materials shrink as they cool, becoming more dense. Since planets cool from the outside in, the crusts are already compressed and compact by the time the interior cools. As the planet's interior cools, its compaction will gradually pull the support out from under the crust.
This creates a tremendous amount of stress on the solid crust, which responds the only way it can: by breaking. some blocks of crust will follow the contracting core downwards. This forces neighboring blocks of crust upward, since there isn't enough space for all the material to drop. The result is a graben, named for the German word for a ditch.
Lots of graben
Grabens were first identified on Earth, where the interior remains warm, and they typically form where the crust has been stretched to the point of breaking. But they have since been identified on various other bodies in the Solar System. The new work, done by a small European team, conducted a comprehensive search for graben in images of Mercury taken by the MESSENGER spacecraft, which ended its mission to the planet eight years ago.
Using the extensive image archive created by MESSENGER, the researchers picked out terrain that shows signs of having been compressed by stresses generated by Mercury's compaction, and then examined this terrain by eye. Within these areas, the researchers identified 727 likely graben, with high confidence in around 200 of them. Once identified, the researchers used shadows to try to estimate the graben's depth in cases where the imaging angle allowed for this.
The mere fact that these ditches haven't been filled in by the processes active on the surface of Mercury (primarily impacts and the formation and spread of regolith) suggests that the graben are fairly young. And the widespread nature of them indicates that tectonic activity is widespread on the planet. The majority of graben seen here are within a large impact crater called the Caloris Basin, where the thinned crust may be more prone to faulting.
Overall, most of the graben were less than 50 meters deep. But a fair number were between 50 and 100 meters deep, and at least 20 were over 100 meters deep. If these were old structures, they simply would not be this deep. Based on a relationship between graben length and depth as seen on the Earth and Moon, the authors estimate that most of the graben are less than 200 million years old and possibly quite a bit younger.
That would mean the cooling of Mercury is likely an ongoing process, one that is still triggering tectonic activity. While we're unlikely to get a lander there any time soon to confirm this, we will get a new view of Mercury starting in 2025, when the ESA's BepiColombo spacecraft goes into orbit. | Chemistry and Material Sciences |
4.6-billion-year-old meteorite increases our understanding of the early solar system
An analysis of the approximately 4.6-billion-year-old meteorite Erg Chech 002, discovered in 2020 in the Erg Chech region of the Sahara Desert in Algeria, is presented in Nature Communications.
In combination with previously published data, Aluminum-26 (26Al), a radioactive isotope that was present within the meteorite when it formed, is found to have been spread unevenly throughout our solar system. The findings increase our understanding of the early solar system and may improve the accuracy of determining the ages of very old meteorites.
Erg Chech 002 is an andesitic achondrite, a type of stony meteorite among the oldest known of to date. 26Al was a major heat source for early planetary melting and Erg Chech 002's old age provides an opportunity to further explore the initial distribution of 26Al within the early solar system. Whether 26Al is distributed evenly throughout the early solar system is important for determining the ages of meteorites, and understanding the early solar system, but is debated.
Evgenii Krestianinov and colleagues analyzed Erg Chech 002 and determined its lead-isotopic age as about 4.566 billion years old. They then combined this finding with existing data for this meteorite and compared this to other very old meteorites that crystallized from melts. The authors demonstrated that 26Al had an uneven distribution within the early Solar Nebula, likely associated with the late infall of stellar materials with freshly synthesized radionuclides.
Krestianinov and co-authors suggest that meteorite chronology studies should be cautious and take a generalized approach for dating with short-lived isotopes that accounts for their uneven distribution to improve the accuracy and reliability of determining the ages of meteorites and planetary materials.
More information: Evgenii Krestianinov et al, Igneous meteorites suggest Aluminium-26 heterogeneity in the early Solar Nebula, Nature Communications (2023). DOI: 10.1038/s41467-023-40026-1
Journal information: Nature Communications
Provided by Nature Publishing Group | Chemistry and Material Sciences |
Mirages have a reputation for deceit. The classic example is the oasis in the desert. Or there's the obstructed view of the iceberg that may have confused the Titanic's captain. The legendary ghost ship, the Flying Dutchman, is also a mirage. But what is a mirage? And are the images that dance on hot roads, stretches of desert, and the sea surface really figments of the imagination, or are they images of real things?
The answer lies in the way the eye interprets the bending light that produces these images.
"It's not an optical illusion," Anthony Young, an astronomer at San Diego State University, told Live Science. That's the thing people get wrong about mirages. The mirage is an image of a real thing — it can even be photographed — but it's often a distorted image, and it's easy to misinterpret. Viewers "don't know what it is, so they misidentify it as something familiar," Young said. For instance, in the desert, mirages that reflect the sky are often misinterpreted as a pool of water.
Even if we misinterpret the mirage, a question remains: How did an image of a real object end up in the wrong place?
The short answer is refraction, the bending of light rays as they travel through different materials. Mirages happen as light waves travel through air at different densities.
When light travels through the same material, it typically travels in a straight line," Xin Tong, a doctoral student in optical imaging at Caltech told Live Science. But when the light encounters a different material, it will bend toward the higher density. Air density depends on temperature, so when light travels through air at different temperatures, it bends toward the cooler air, which is denser.
This creates two kinds of mirages. The first, a superior mirage, is what you see in the spring and summer when the sea is much cooler than the summer's hot air, Tong said. It's what historians suspect happened over freezing water the night the Titanic sank. In either case, the air closest to the water is colder than the air above it. The air gets warmer as you move away from sea level. This creates a temperature and density gradient, causing the light reflected by an object — like a ship, an iceberg or a nearby island — to bend.
The light bending toward the colder, sea-level air creates the mirage. It causes the object to appear higher than it really is, Tong said. That's because your eye expects light to travel in a straight line, so it interprets the object as in a different spot because of the bending light. When these superior mirages are particularly vivid and changing, which can happen over the open ocean, they also go by the Italian name "fata morgana," or "Morgan the Fairy." The Flying Dutchman is suspected of being a fata morgana.
The other type of mirage, an inferior mirage, is what happens in the desert or on hot pavement when the surface and nearby air are warmer than the air above it. To see these mirages, you need to be above the warmest air layer. And light coming from above bends upward toward the cooler air. Again, because the eye anticipates that light will travel in a straight line, it interprets the image as lower and inverted, Tong said. This is how an image of the sky can appear like a water surface on the desert floor.
In both cases, seeing the mirage is highly dependent on position and receiving angle. A small change in position can cause the optical phenomenon to disappear, Tong said.
Inferior mirages are easier to find if you know where to look. But the more spectacular mirages can be finicky. "Superior mirages are only seen sometimes in an interval of a few centimeters," Young said. And there's really a very short window for them to appear — only 10 to 15 minutes. But they're "nice to look at when you can find them," he said.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Donavyn Coffey is a Kentucky-based health and environment journalist reporting on healthcare, food systems and anything you can CRISPR. Her work has appeared in Scientific American, Wired UK, Popular Science and Youth Today, among others. Donavyn was a Fulbright Fellow to Denmark where she studied molecular nutrition and food policy. She holds a bachelor's degree in biotechnology from the University of Kentucky and master's degrees in food technology from Aarhus University and journalism from New York University. | Chemistry and Material Sciences |
Biological fingerprints in soil show where diamond-containing ore is buried
Researchers have identified buried kimberlite, the rocky home of diamonds, by testing the DNA of microbes in the surface soil.
These "biological fingerprints" can reveal which minerals are buried tens of meters below Earth's surface without having to drill. The researchers believe it is the first use of modern DNA sequencing of microbial communities in the search for buried minerals.
The research published in Communications Earth and Environment represents a new tool for mineral exploration, where a full toolbox could save prospectors time and a lot of money, says co-author Bianca Iulianella Phillips, a doctoral candidate at UBC's department of Earth, ocean and atmospheric sciences (EOAS).
The technique adds to the relatively limited number of tools that help find buried ore, including initial scans of the ground and analysis of elements in the overlying rock.
"This technique was born from a necessity to see through the Earth with greater sensitivity and resolution, and it has the potential to be used where other techniques aren't working," said Phillips.
When ore interacts with soil, it changes the communities of microbes in the soil. The researchers tested this in the lab, introducing kimberlite to soil microbes and watching how they changed in number and species.
"We took those changed communities of microbes as indicators for the presence of ore materials, or biological fingerprints in the soil of buried mineral deposits," said Phillips.
Using these "indicator" microbes and their DNA sequences, the team tested the surface soil at an exploration site in the Northwest Territories where kimberlite had previously been confirmed through drilling. They found 59 of the 65 indicators were present in the soil, with 19 present in high numbers directly above the buried ore. They also identified new indicator microbes to add to their set.
Using this set, they tested the surface soil at a second site in the Northwest Territories where they suspected kimberlite was present, and precisely located the topological outline and location of kimberlite buried tens of meters beneath the Earth's surface. This showed that indicators from one site could predict the location at another site. In future, exploration teams could build up a database of indicator species and test an unknown site to find out if kimberlite deposits are buried beneath the soil.
The researchers evaluated their technique against another technique known as geochemical analysis, which involves testing elements in the soil to identify the minerals beneath. The microbes were more precise when it came to identifying the location of buried ore.
"Microbes are better geochemists than us, and there are thousands of them," said lead author Dr. Rachel Simister, who conducted the work as a postdoctoral researcher in the UBC department of microbiology and immunology (M&I). "You might run out of elements to sample, but you'll never run out of microbes."
The technique, born from work by a team including Phillips, Dr. Simister, Dr. Sean Crowe and the late professor Peter Winterburn, could catalyze the discovery of new kimberlite deposits. These rocks are known not only as potential stores of diamonds, but also for their ability to capture and store atmospheric carbon.
The technique has potential application across other metallic deposits. The team's ongoing research shows similar results for identifying porphyry copper deposits.
"You could use this technique to find minerals to fuel a green economy," said senior author Dr. Crowe, EOAS and M&I professor and Canada Research Chair in Geomicrobiology. "Copper is the most important critical element that we'll need more of going forward."
"This is exciting because it's part of a growing recognition of the potential for using microbes at every stage of mining, from finding the minerals, to processing them, to returning sites to their natural states." said Dr. Crowe. "Currently, microbial DNA sequencing requires specific expertise and is comparable in cost to other mineral exploration techniques, but this could change with industry adoption."
More information: Rachel L. Simister et al, DNA sequencing, microbial indicators, and the discovery of buried kimberlites, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-01020-z
Journal information: Communications Earth & Environment
Provided by University of British Columbia | Chemistry and Material Sciences |
James Webb spots carbon on Europa, boosting case for life
The best places in our solar system to search for life beyond Earth aren’t planets like Mars – they’re icy moons like Europa. The case for life on this watery world just got stronger, as the James Webb Space Telescope has detected a fresh carbon source there.
It might not look very hospitable, but Jupiter’s moon Europa is high on the list of promising places to find extraterrestrial life. Astronomers believe that beneath its icy shell lies a global ocean that’s surprisingly similar to those here on Earth. And where there are Earth-like conditions, there could be Earth-like lifeforms.
Now, the James Webb telescope has discovered new evidence of carbon, an element that’s essential for life as we know it, on Europa. And most importantly, it appears to have come from the ocean below, rather than meteorites or other sources from above.
“We now think that we have observational evidence that the carbon we see on Europa’s surface came from the ocean," said Samantha Trumbo, lead author of a study analyzing the data. "That's not a trivial thing. Carbon is a biologically essential element."
The discovery was made using the spacecraft’s Near-Infrared Spectrograph (NIRSpec) instrument, which took infrared measurements of the moon’s surface. Scientists can then analyze the specific patterns of how the light reflects back to determine which specific chemicals are present and where they are.
In doing so, the team found large deposits of crystallized carbon dioxide and complex, amorphous carbon dioxide in several regions of Europa’s surface. The CO2 is most abundant in an area called Tara Regio, which is marked with “chaos terrain” where the surface ice is disrupted and interacts with the subsurface ocean below. Bolstering the ocean origin hypothesis is the fact that CO2 isn’t stable on the surface, indicating it was deposited there relatively recently.
“Previous observations from the Hubble Space Telescope show evidence for ocean-derived salt in Tara Regio,” said Trumbo. “Now we’re seeing that carbon dioxide is heavily concentrated there as well. We think this implies that the carbon probably has its ultimate origin in the internal ocean.”
Previous studies have detected what could be plumes of water shooting out through the ice from the ocean below, which could be one mechanism for how the carbon dioxide ends up on the ice. These observations didn’t catch any plumes in the act though, but that doesn’t mean there aren’t any – just that they could be intermittent.
More evidence for the presence of life on this intriguing icy moon could be discovered sooner rather than later, as NASA plans to launch the Europa Clipper mission in October 2024.
Source: NASA | Chemistry and Material Sciences |
By Steve Gorman
(Reuters) - NASA was set on Wednesday to provide a first peek for the public at what scientists found inside a tightly sealed canister that was returned to Earth last month carrying the largest soil sample ever scooped up from the surface of an asteroid.
The material collected by the OSRIS-REx spacecraft three years ago from the near-Earth asteroid Bennu was to be unveiled at NASA's Johnston Space Center in Houston, a little more than two weeks after it was parachuted into the Utah desert.
The landing of the return capsule capped a six-year joint mission of the U.S. space agency and the University of Arizona. It was only the third asteroid sample, and by far the biggest, ever returned to Earth for analysis, following two similar missions by Japan's space agency ending in 2010 and 2020.
Like other asteroids, Bennu is a relic of the early solar system. Because its present-day chemistry and mineralogy are virtually unchanged since forming some 4.5 billion years ago, it holds clues to the origins and development of rocky planets such as Earth, and perhaps even the evolution of life.
The capsule and its contents were initially examined in a "clean room" at the Utah Test and Training range near the landing site. The capsule was then flown to the Johnson center, where its inner canister was opened in order for samples to be parceled into smaller specimens promised to some 200 scientists in 60 laboratories around the world.
At the time it landed, the Bennu sample was estimated to weigh about 100 to 250 grams (3.5 to 8.8 ounces).
NASA was expected to announce a more precise measurement on Wednesday, along with a confirmation of whether the goal of collecting a pristine sample, totally free of terrestrial contamination, was achieved.
Physical characteristics such as the material's density, color and form - whether consisting of rocks, pebbles, fine grains or dust - are also expected to be revealed.
Samples returned in 2020 by the Japanese mission Hayabusa2 from Ryugu, another near-Earth asteroid, were found to contain two organic compounds, buttressing the hypothesis that celestial objects such as comets, asteroids and meteorites that bombarded early Earth seeded the young planet with the primordial ingredients for life.
Bennu, a small, carbon-rich body discovered in 1999, appears to be made up of a loose collection of rocks, like a rubble pile, according to scientists. It measures about three-tenths of a mile (500 meters) across, making it slightly wider than the Empire State Building is tall but tiny compared with the Chicxulub asteroid that struck Earth some 66 million years ago, wiping out the dinosaurs.
OSIRIS-REx launched in 2016 and reached Bennu in 2018, then spent nearly two years orbiting the asteroid before venturing close enough to snatch a sample of the loose surface material with its robotic arm on Oct. 20, 2020.
NASA is due to launch a separate mission on Thursday to a more distant asteroid called Psyche, a metal-rich body believed to be the remnant core of a protoplanet and the largest known metallic object in the solar system.
(Reporting by Steve Gorman in Los Angeles; Editing by Will Dunham) | Chemistry and Material Sciences |
Galactic archaeology uncovers the dramatic history of our next-door neighbor, the Andromeda galaxy
Research led by the University of Hertfordshire has revealed the dramatic history of Andromeda, our nearest neighboring galaxy. Using state-of-the-art modeling, Professor Chiaki Kobayashi and a team of international astrophysicists have determined details about the galaxy's history through galactic archaeology—an approach that examines the chemical composition of stars and the development of their host galaxy, to reconstruct its past.
The study, accepted for publication in The Astrophysical Journal Letters and available on the arXiv preprint server, examines the elemental abundances in Andromeda, in particular the presence of both planetary nebulae—gas and dust that are formed from the cast-off outer layers of dying low-mass stars—and red-giant branch stars.
The analysis reveals that Andromeda's formation was more dramatic and forceful than that of our own Milky Way. After an initial intense burst of star formation that created the galaxy, a secondary layer of stars was produced between 2 billion and 4.5 billion years ago, most likely triggered by what scientists call a "wet merger"—a merging of two, gas-rich galaxies that instigates a large amount of star formation.
Scientists have long thought it likely that Andromeda experienced a merger of two galaxies, based on the position and motion of individual stars in the galaxy. Professor Kobayashi's research shines new light on the nature and impact of such a merger using the chemical composition of stars—and explains how stars and elements were formed throughout the history of Andromeda.
Professor Kobayashi, Professor of Astrophysics at the University of Hertfordshire's Center for Astrophysics Research, said, "This is a fantastic example of how galactic archaeology can provide fresh new insights into the history of our universe. By analyzing the chemical abundance in different ages of stars in Andromeda, we can bring to life its history and better understand its origins.
"Although in many ways Andromeda is similar to our own Milky Way—it's a similarly-sized, spiral disk galaxy—our new research confirms that its history is far more intense and dramatic, with bursts of activity forming stars in abundance, and two distinct eras of star formation."
Professor Kobayashi's theoretical model predicts two distinct chemical compositions of stars in the two disk components of Andromeda—one has ten times more oxygen than iron, while another has a similar amount of oxygen and iron. This modeling has been confirmed by the spectroscopic observations of planetary nebulae, and also by those of red-giant stars with the James Webb Space Telescope (JWST).
The new study continues Professor Kobayashi's ongoing research into the origin of elements in the universe. As she explains, "Oxygen is one of the so-called alpha-elements produced by massive stars. The others are neon, magnesium, silicon, sulfur, argon, and calcium.
"Oxygen and argon have been measured with planetary nebulae, but Andromeda is so far away that JWST is required to measure other elements, including iron. In coming years, JWST and ground-based large telescopes will keep looking at Andromeda—giving further weight to the new findings."
More information: Chiaki Kobayashi et al, On the α/Fe bimodality of the M31 disks, arXiv (2023). DOI: 10.48550/arxiv.2309.01707
Provided by University of Hertfordshire | Chemistry and Material Sciences |
In just under 14 Earth days, Chandrayaan-3 provided scientists with valuable new data and further inspiration to explore the Moon. And the Indian Space Research Organization has shared these initial results with the world.
While the data from Chandrayaan-3's rover, named Pragyan, or "wisdom" in Sanskrit, showed the lunar soil contains expected elements such as iron, titanium, aluminum and calcium, it also showed an unexpected surprise – sulfur.
Planetary scientists like me have known that sulfur exists in lunar rocks and soils, but only at a very low concentration. These new measurements imply there may be a higher sulfur concentration than anticipated.
Pragyan has two instruments that analyze the elemental composition of the soil – an alpha particle X-ray spectrometer and a laser-induced breakdown spectrometer, or LIBS for short. Both of these instruments measured sulfur in the soil near the landing site.
Sulfur in soils near the Moon's poles might help astronauts live off the land one day, making these measurements an example of science that enables exploration.
Geology of the Moon
There are two main rock types on the Moon's surface – dark volcanic rock and the brighter highland rock. The brightness difference between these two materials forms the familiar "man in the moon" face or "rabbit picking rice" image to the naked eye.
Scientists measuring lunar rock and soil compositions in labs on Earth have found that materials from the dark volcanic plains tend to have more sulfur than the brighter highlands material.
Sulfur mainly comes from volcanic activity. Rocks deep in the Moon contain sulfur, and when these rocks melt, the sulfur becomes part of the magma. When the melted rock nears the surface, most of the sulfur in the magma becomes a gas that is released along with water vapor and carbon dioxide.
Some of the sulfur does stay in the magma and is retained within the rock after it cools. This process explains why sulfur is primarily associated with the Moon's dark volcanic rocks.
Chandrayaan-3's measurements of sulfur in soils are the first to occur on the Moon. The exact amount of sulfur cannot be determined until the data calibration is completed.
The uncalibrated data collected by the LIBS instrument on Pragyan suggests that the Moon's highland soils near the poles might have a higher sulfur concentration than highland soils from the equator and possibly even higher than the dark volcanic soils.
These initial results give planetary scientists like me who study the Moon new insights into how it works as a geologic system. But we'll still have to wait and see if the fully calibrated data from the Chandrayaan-3 team confirms an elevated sulfur concentration.
Atmospheric sulfur formation
The measurement of sulfur is interesting to scientists for at least two reasons. First, these findings indicate that the highland soils at the lunar poles could have fundamentally different compositions, compared with highland soils at the lunar equatorial regions. This compositional difference likely comes from the different environmental conditions between the two regions – the poles get less direct sunlight.
Second, these results suggest that there's somehow more sulfur in the polar regions. Sulfur concentrated here could have formed from the exceedingly thin lunar atmosphere.
The polar regions of the Moon receive less direct sunlight and, as a result, experience extremely low temperatures compared with the rest of the Moon. If the surface temperature falls, below -73 degrees C (-99 degrees F), then sulfur from the lunar atmosphere could collect on the surface in solid form – like frost on a window.
Sulfur at the poles could also have originated from ancient volcanic eruptions occurring on the lunar surface, or from meteorites containing sulfur that struck the surface and vaporized on impact.
Lunar sulfur as a resource
For long-lasting space missions, many agencies have thought about building some sort of base on the Moon. Astronauts and robots could travel from the south pole base to collect, process, store and use naturally occurring materials like sulfur on the Moon – a concept called in-situ resource utilization.
In-situ resource utilization means fewer trips back to Earth to get supplies and more time and energy spent exploring. Using sulfur as a resource, astronauts could build solar cells and batteries that use sulfur, mix up sulfur-based fertilizer and make sulfur-based concrete for construction.
For one, sulfur-based concrete hardens and becomes strong within hours rather than weeks, and it's more resistant to wear. It also doesn't require water in the mixture, so astronauts could save their valuable water for drinking, crafting breathable oxygen and making rocket fuel.
While seven missions are currently operating on or around the Moon, the lunar south pole region hasn't been studied from the surface before, so Pragyan's new measurements will help planetary scientists understand the geologic history of the Moon. It'll also allow lunar scientists like me to ask new questions about how the Moon formed and evolved.
For now, the scientists at Indian Space Research Organization are busy processing and calibrating the data. On the lunar surface, Chandrayaan-3 is hibernating through the two-week-long lunar night, where temperatures will drop to -184 degrees F (-120 degrees C). The night will last until September 22.
There's no guarantee that the lander component of Chandrayaan-3, called Vikram, or Pragyan will survive the extremely low temperatures, but should Pragyan awaken, scientists can expect more valuable measurements.
Jeffrey Gillis-Davis, Research Professor of Physics, Arts & Sciences at Washington University in St. Louis | Chemistry and Material Sciences |
GHOST finds an extremely metal-poor star
An international team of astronomers reports the detection of a new extremely metal-poor star using the Gemini High-resolution Optical SpecTrograph (GHOST) at the Gemini South telescope in Chile. The finding was presented in a paper published October 25 on the pre-print server arXiv.
Metal-poor stars are rare objects as only a few thousands of stars with iron abundances [Fe/H] below -2.0 have been discovered to date. Expanding the still short list of metal-poor stars is of high importance for astronomers as such objects have the potential to improve our knowledge of chemical evolution of the universe.
Located some 25,500 light years away from the Earth, SPLUS J142445.34−254247.1, or SPLUS J1424−2542 for short, was detected in 2019 as part of the Southern Photometric Local Universe Survey (S-PLUS). The star has a mass of about 0.84 solar masses, is estimated to be 10 billion years old, and its effective temperature is approximately 4,750 K.
Previous studies of SPLUS J1424−2542 have suggested that its metallicity is at a level of -3.25, therefore it should be classified as an extremely metal-poor star.
Now, a group of astronomers led by Vinicius M. Placco of the University of São Paulo in Brazil, has conducted GHOST observations of SPLUS J1424−2542, which allowed them to perform a chemical study of this star confirming this hypothesis.
"High-resolution spectroscopy was gathered with GHOST at Gemini South, allowing for the determination of chemical abundances for 36 elements, from carbon to thorium," the researchers wrote in the paper.
The GHOST spectrum of SPLUS J1424−2542 allowed the team to detect 308 absorption features for 36 elements. The metallicity of this star was found to be approximately -3.39, which confirms its extremely metal-poor nature.
The study found that SPLUS J1424−2542 shows enhancement in heavy elements. This, together with its low metallicity and carbon to iron ratio at a level of 0.06, indicates that the star most likely was formed from a gas cloud polluted by at least two progenitor populations—the supernova explosion from a metal-free star (with an estimated mass of about 11.3–13.4 solar masses) and the aftermath of a binary neutron star merger with masses of about 1.66 and 1.27 solar masses.
The results suggest that SPLUS J1424−2542 has an effective temperature of 4,762 K, which is consistent with previous studies. The total space velocity of this star was calculated to be approximately 108 km/s.
Summing up the result, the authors of the paper concluded that SPLUS J1424−2542, besides being extremely metal-poor, is a low-mass, old star, which belongs to the in-situ Galactic halo population.
More information: Vinicius M. Placco et al, SPLUS J142445.34-254247.1: An R-Process Enhanced, Actinide-Boost, Extremely Metal-Poor star observed with GHOST, arXiv (2023). DOI: 10.48550/arxiv.2310.17024
Journal information: arXiv
© 2023 Science X Network | Chemistry and Material Sciences |
It is a mystery that has gripped humanity for hundreds of years — how exactly did our moon come to be?
Since the 1970s, astronomers have suspected that our natural satellite was created when a giant protoplanet called Theia struck early Earth (Gaia).
The nature of this collision and what happened immediately after has been subject to debate, however, with some scientists suggesting that it created a vast cloud of debris which coalesced into the moon over time.
Now, new evidence has been uncovered which supports the impact theory 4.5 billion years ago — as well as revealing a rather surprising fact about our own planet.
Not only did the collision create the moon, a new study says, but it also buried relics of Theia deep within Earth's mantle, which ultimately went on to help form Hawaii and Iceland.
Astronomers have long suspected that the moon was created when a giant protoplanet called Theia struck the newly formed Earth - a theory first put forward in the 1970s. It says the huge collision created a vast cloud of debris, which coalesced into the moon. However, until now, astronomers have not been able to explain how this left the moon and Earth chemically identical. Later, two hypotheses arose that could explain why the moon is Earth's chemical clone, but they predict radically different masses for Theia. In one scenario, two half-Earths merged to form the Earth-moon system. But the second hypothesis suggests Theia was a small, high-velocity projectile that smacked into a large and fast-spinning young Earth.
Researchers led by the California Institute of Technology said these relics from the Mars-sized protoplanet would have been thousands of miles across.
They think the dense material sank to the lower region of the Earth's mantle, where it pooled together to form heavy blobs above our planet's core that still exist today.
The scientists came to their conclusion with the help of computer simulations which aimed to explain why there is a massive anomaly deep within the Earth's interior.
There are two regions at the base of our planet's mantle which are unusual and different to the rest of the layer.
Known as Large Low Velocity Provinces (LLVPs), one is located beneath the African tectonic plate and the other under the Pacific tectonic plate.
Their existence was established when geologists found that seismic waves slowed dramatically at a depth of 1,800 miles (2,900 km) in the two regions, which differed to other parts of the Earth.
Scientists believe the material in these LLVPs is between 2 and 3.5 per cent denser than the surrounding mantle.
The regions are important because they would have played a key role in how the mantle evolved, which in turn would have affected the formation of supercontinents and Earth's tectonic plates.
How they came to be, however, is very much a mystery.
Aware of the theory for the moon's formation, lead author Qian Yuan and his colleagues came up with the idea that LLVPs could have evolved from a small amount of Theian material that entered Gaia's lower mantle.
To back this up they asked Professor Hongping Deng, of the Shanghai Astronomical Observatory, to explore this idea with the help of his pioneering methods in computational fluid dynamics.
After running a series of simulations, Professor Deng discovered that following the moon-forming impact a significant amount of Theian mantle material – around two per cent of Earth's mass – entered the lower mantle of Gaia.
He added that the impact appeared to have been 'the starting point for the Earth's geological evolution over the course of 4.5 billion years.'
Researchers also calculated that this lunar rock-like material is likely enriched with iron, making it denser than the surrounding Gaian material.
This, they said, is what caused it to sink to the bottom of the mantle and ultimately form the two LLVP regions which have remained stable despite 4.5 billion years of geological evolution.
It also suggests that the Earth's interior it not a 'boring', uniform system but actually a mix of material that can be brought to the surface to form landmasses such as Hawaii and Iceland.
'Through precise analysis of a wider range of rock samples, combined with more refined giant impact models and Earth evolution models, we can infer the material composition and orbital dynamics of the primordial Earth, Gaia, and Theia,' said Dr Yuan.
'This allows us to constrain the entire history of the formation of the inner solar system.'
Not only that, but because giant impacts are common at the end of a planet's formation, scientists say similar mantle differences may also exist in the interiors of other planetary bodies in our solar system and beyond.
The new study has been published in the journal Nature. | Chemistry and Material Sciences |
Astronomers detected a potent space explosion this year and directed the powerful James Webb Space Telescope at the cosmic blast.
This blast was a "gamma-ray burst" containing the most energetic type of light that's often generated by the collapse and explosion of enormous stars, events called supernovae. But the eruption in March 2023, dubbed "GRB 230307A," wasn't any ordinary gamma-ray burst. It was 1,000 times brighter than the typically observed burst, and the rays hit our instruments for a whopping two minutes. Usually, they last just two seconds.
In new research published in the peer-reviewed journal Nature, scientists conclude that a momentous type of explosion called a "kilonova" created the blast. And researchers suspect two curious objects called neutron stars — objects so incredibly dense that a teaspoon of neutron star weighs around a whopping 1 billion tons — collided, triggering the explosion.
Crucially, astronomers theorize that important elements and metals, like gold and platinum, are forged in these outbursts. In this kilonova, the Webb telescope detected the rare element tellurium, which on Earth is rarer than platinum (and platinum is some 30 times rarer than gold).
It's a significant find. The same blast likely made other elements close to tellurium like iodine, "which is needed for much of life on Earth," NASA explains.
"Just over 150 years since Dmitri Mendeleev wrote down the periodic table of elements, we are now finally in the position to start filling in those last blanks of understanding where everything was made, thanks to Webb," Andrew Levan, an astrophysicist at Radboud University in the Netherlands and the University of Warwick in the UK who led the research, said in a statement.
In the Webb telescope image below, you can see the source of the potent gamma-ray burst. That red dot is the distant kilonova. Other instruments, like NASA’s gamma-ray-detecting Swift observatory, allowed the researchers to pinpoint the source of the blast. To the right is the galaxy where these dense, massive neutron stars originated.
Below the image is a graphic showing how Webb detected the rare, heavy metal tellurium, which was likely forged in this outburst. One of Webb's most vital investigative instruments is its spectrograph, called NIRSpec (Near-Infrared Spectrograph). This instrument separates out the types of light coming from an object, similar to a prism separating visible light into a rainbow of colors. Certain wavelengths, or types of light, correspond to different elements or molecules. In this case, the Webb's spectrum showed clear signs that tellurium was present in that kilonova.
In the coming years, astronomers expected to find more rare, heavy metals, forged by explosions in the deep cosmos.
"Webb has certainly opened the door to do a lot more, and its abilities will be completely transformative for our understanding of the universe," Ben Gompertz, an astronomer at the University of Birmingham who worked on the research, said in a statement.
The Webb telescope's powerful abilities
The Webb telescope — a scientific collaboration between NASA, the ESA, and the Canadian Space Agency — is designed to peer into the deepest cosmos and reveal new insights about the early universe. But it's also peering at intriguing planets in our galaxy, along with the planets and moons in our solar system.
Want more science and tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newsletter today.
Here's how Webb is achieving unparalleled feats, and likely will for decades:
- Giant mirror: Webb's mirror, which captures light, is over 21 feet across. That's over two and a half times larger than the Hubble Space Telescope's mirror. Capturing more light allows Webb to see more distant, ancient objects. As described above, the telescope is peering at stars and galaxies that formed over 13 billion years ago, just a few hundred million years after the Big Bang.
"We're going to see the very first stars and galaxies that ever formed," Jean Creighton, an astronomer and the director of the Manfred Olson Planetarium at the University of Wisconsin–Milwaukee, told Mashable in 2021.
- Infrared view: Unlike Hubble, which largely views light that's visible to us, Webb is primarily an infrared telescope, meaning it views light in the infrared spectrum. This allows us to see far more of the universe. Infrared has longer wavelengths than visible light, so the light waves more efficiently slip through cosmic clouds; the light doesn't as often collide with and get scattered by these densely packed particles. Ultimately, Webb's infrared eyesight can penetrate places Hubble can't.
"It lifts the veil," said Creighton.
- Peering into distant exoplanets: The Webb telescope carries specialized equipment called spectrographs that will revolutionize our understanding of these far-off worlds. The instruments can decipher what molecules (such as water, carbon dioxide, and methane) exist in the atmospheres of distant exoplanets — be they gas giants or smaller rocky worlds. Webb will look at exoplanets in the Milky Way galaxy. Who knows what we'll find?
"We might learn things we never thought about," Mercedes López-Morales, an exoplanet researcher and astrophysicist at the Center for Astrophysics-Harvard & Smithsonian, told Mashable in 2021.
Already, astronomers have successfully found intriguing chemical reactions on a planet 700 light-years away, and as described above, the observatory has started looking at one of the most anticipated places in the cosmos: the rocky, Earth-sized planets of the TRAPPIST solar system.
Topics NASA | Chemistry and Material Sciences |
New observations down to light-year scale of the gas flows around a supermassive black hole have successfully detected dense gas inflows and shown that only a small portion (about 3 percent) of the gas flowing towards the black hole is eaten by the black hole. The remainder is ejected and recycled back into the host galaxy.
Not all of the matter which falls towards a black hole is absorbed, some of it is ejected as outflows. But the ratio of the matter that the black hole "eats," and the amount "dropped" has been difficult to measure.
An international research team led by Takuma Izumi, an assistant professor at the National Astronomical Observatory of Japan, used the Atacama Large Millimeter/submillimeter Array (ALMA) to observe the supermassive black hole in the Circinus Galaxy, located 14 million light-years away in the direction of the constellation Circinus. This black hole is known to be actively feeding.
Thanks to ALMA's high resolution, the team was the first in the world to measure the amount of inflow and outflow down to a scale of a few light-years around the black hole. By measuring the flows of gasses in different states (molecular, atomic, and plasma) the team was able to determine the overall efficiency of black hole feeding, and found that it was only about 3 precent. The team also confirmed that gravitational instability is driving the inflow. Analysis also showed that the bulk of the expelled outflows are not fast enough to escape the galaxy and be lost. They are recycled back into the circumnuclear regions around the black hole, and start to slowly fall towards the black hole again.
Story Source:
Journal Reference:
Cite This Page: | Chemistry and Material Sciences |
It is the cloud that overshadows the search for alien life: for all the spacecraft sent to faraway worlds, researchers do not really know what to look for when it comes to evidence of life elsewhere.
Now, scientists are claiming progress with the puzzle after training a computer program to distinguish chemical mixtures made by living organisms from those created in more prosaic processes, such as reactions between sunlight and rocks.
In preliminary tests, the program was 90% accurate at telling the difference between samples taken from living organisms, such as shells, teeth and bones, and non-biological samples, such as laboratory chemicals and those found in carbon-rich meteorites.
Unless alien life wanders in front of a robotic lander’s camera, leaves an unambiguous fossil in a rock, or a smear of proteins on a distant world’s surface, such chemical “biosignatures” may be the best hope scientists have of finding past or present life.
Dr Robert Hazen, an astrobiologist at the Carnegie Institution for Science in Washington DC and a senior scientist on the project, said the tool had the potential to revolutionise the search for extraterrestrial life and deepen the understanding of the origins and chemistry of life on Earth.
Armed with the technique, the researchers hope to analyse materials from Mars for signs of life and bring clarity to raging debates over samples considered to be candidates for the earliest known life on Earth.
The researchers set out to build the signs-of-life detector after reasoning that life, unlike non-living material such as rocks, is built from molecules that are selected for their function. Based on that thinking, the molecular make-up of life past or present should differ from that of objects that have never been alive.
To explore the idea, the scientists ran 134 diverse samples from living and non-living objects through a process called pyrolysis-GC-MS. This provided a breakdown of the organic molecules in each sample. Using machine learning and mathematical modelling they then trained an algorithm to distinguish between samples of biological and non-biological origins. To the researchers’ surprise, the program identified three groups of samples: non-biological, life and fossilised life.
“There is something fundamentally different about the distributions of molecules in living versus non-living systems,” said Hazen. “The analytical method is so simple and so widely used in industry, forensics and science that we think the machine learning approach could prove immensely powerful.”
The scientists are now working with 25 leading palaeobiologists to see what the program makes of some of the oldest candidates for life on Earth. One is a 3.5bn-year-old slab of rock from Western Australia that some researchers believe contains some of the oldest fossilised microbes on the planet.
With further training, the tool may learn to distinguish different types of life, such as photosynthetic life from other organisms, the scientists say. Details are published in Proceedings of the National Academy of Science.
The researchers hope to expand their tests to Mars samples already collected by Nasa’s Curiosity rover. Whether the program can spot signs of any kind of life, or merely life as we know it, is unknown.
Hazen suspects all life may use molecules differently to non-living objects and so reveal itself under analysis, regardless of its biology. “We may be able to find a lifeform from another planet, another biosphere, even if it is very different from the life we know on Earth,” he said. | Chemistry and Material Sciences |
An international team of astronomers led by the University of Cambridge has used data from the NASA/ESA/CSA James Webb Space Telescope to discover methane and carbon dioxide in the atmosphere of K2-18 b, an exoplanet in the ‘Goldilocks zone’. This is the first time that carbon-based molecules have been discovered in the atmosphere of an exoplanet in the habitable zone.
The results are consistent with an ocean-covered surface underneath a hydrogen-rich atmosphere. The discovery provides a glimpse into a planet unlike anything else in our Solar System, and raises interesting prospects about potentially habitable worlds elsewhere in the Universe.
K2-18 b — which is 8.6 times as massive as Earth — orbits the cool dwarf star K2-18 in the habitable zone and lies 110 light years from Earth in the constellation of Leo. A first insight into the atmosphere of K2-18 b came from observations with the Hubble Space Telescope but the atmospheric composition has been a subject of debate. The same researchers studied K2-18 b in 2020 and 2021, and identified it as belonging to a new class of habitable exoplanets called ‘Hycean’ worlds which could accelerate the search for life elsewhere. This prompted them to take a more detailed look with JWST, Hubble’s successor.
Using JWST’s higher resolution instruments, this new investigation has definitively identified methane and carbon dioxide in a hydrogen-rich atmosphere on K2-18 b.
The researchers also identified another, weaker, signal in the K2-18 b spectrum. After several analyses, the researchers say that the signal could be caused by a molecule called dimethyl sulphide (DMS). On Earth, DMS is only produced by life, primarily microbial life such as marine phytoplankton, suggesting the possibility of biological activity on K2-18 b. While these signs of DMS are tentative and require further validation, the researchers say that K2-18 b and other Hycean planets could be our best chance to find life outside our Solar System.
The results, which have been accepted for publication in The Astrophysical Journal Letters, will be presented today (11 September) at the First Year of JWST Science Conference in Baltimore, Maryland, USA.
Exoplanets such as K2-18 b, which have sizes between those of Earth and Neptune, are unlike anything in our Solar System. This lack of analogous nearby planets means that these ‘sub-Neptunes’ are poorly understood and the nature of their atmospheres is a matter of active debate between astronomers.
“Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” said lead author Professor Nikku Madhusudhan, from Cambridge’s Institute of Astronomy. “Traditionally, the search for life on exoplanets has focused primarily on rocky planets, but Hycean worlds are significantly more conducive to atmospheric observations.”
The abundance of methane and carbon dioxide, and dearth of ammonia, are consistent with the presence of an ocean underneath a hydrogen-rich atmosphere in K2-18 b. The inference of DMS, however, is less robust and requires further validation. “More observations are needed to determine whether it is in fact DMS that we’re seeing,” said Madhusudhan. “The possibility of DMS in the atmosphere is highly promising, but we are planning to take another look to robustly establish its presence.”
While K2-18 b looks like a highly promising candidate in the search for life elsewhere, it is possible that it may not be able to support life. The planet’s large size — with a radius 2.6 times the radius of Earth — means that the planet’s interior likely contains a large mantle of high-pressure ice, like Neptune, but with a thinner hydrogen-rich atmosphere and an ocean surface. It is possible that the ocean is too hot to be habitable or be liquid. More observations and theoretical work are needed to establish this conclusively.
“Although this kind of planet does not exist in our Solar System, sub-Neptunes are the most common type of planet known so far in the galaxy,” said co-author Subhajit Sarkar of Cardiff University. “We have obtained the most detailed spectrum of a habitable-zone sub-Neptune to date and this allowed us to work out the molecules that exist in its atmosphere.”
Characterising the atmospheres of exoplanets like K2-18 b — meaning identifying their constituent gases and physical conditions — is an area of frenzied activity in astronomy. Determining the chemicals present in the atmospheres of exoplanets is vital to understanding these alien worlds and provides tantalising hints about habitability elsewhere in the Universe. However, these planets are outshone — literally — by the glare of their much larger parent stars, which makes exploring exoplanet atmospheres challenging.
The team sidestepped this challenge by analysing light from K2-18 b’s parent star as it passed through the exoplanet’s atmosphere. K2-18 b is a transiting exoplanet, meaning that we can detect a drop in the stellar brightness as it passes across the face of its host star. This is how the exoplanet was first discovered in 2015. This means that during transits a tiny fraction of starlight will pass through the exoplanet’s atmosphere before reaching Earth. The starlight’s passage through the atmosphere leaves ghostly traces in the stellar spectrum that astronomers can piece together to determine the constituent gases of the exoplanet’s atmosphere.
“This result was only possible because of the extended wavelength range and unprecedented sensitivity of Webb, which enabled robust detection of spectral features with just two transits,” said Madhusudhan. “For comparison, one transit observation with Webb provided comparable precision to eight observations with Hubble conducted over a few years in a shorter wavelength range.”
“These results are the product of just two observations of K2-18 b, with many more on the way,” said co-author Savvas Constantinou, also from Cambridge’s Institute of Astronomy. “This means our work here is but an early demonstration of what Webb can observe in habitable zone exoplanets.”
The team now intends to conduct follow-up research that they hope will further validate their findings and provide new insights into the environmental conditions on K2-18 b. The team's next round of Webb observations will use the telescope's Mid-InfraRed Instrument (MIRI) spectrograph to scour K2-18 b's atmosphere for tell-tale chemical signatures called biomarkers, including DMS, which could potentially indicate the presence of biological activity.
“Our ultimate goal is the identification of life on a habitable exoplanet, which would transform our understanding of our place in the Universe,” said Madhusudhan. “Our findings are a promising first step in this direction.”
Reference:
Nikku Madhusudhan et al. ‘Carbon-bearing Molecules in a Possible Hycean Atmosphere.’ Paper presented at The First Year of JWST Science Conference. Baltimore, Maryland, USA.
Adapted from a story by the European Space Agency (ESA).
Image credits:
Top: Amanda Smith, Nikku Madhusudhan (University of Cambridge)
Bottom: NASA, CSA, ESA, J. Olmstead (STScI), N. Madhusudhan (University of Cambridge)
Design by Sarah Collins | Chemistry and Material Sciences |
In Virgin Valley, Nevada, it's possible to spend an afternoon digging for rare black fire opals, while visitors to Coalinga, California, can scour the dirt for pieces of the state's official gemstone, benitoite. At Arkansas' Crater of Diamonds State Park, aspiring gemhounds pay just $10 to hunt for the world's most sought-after stones.
Each of these outings requires little more than hand tools, yet most gemstones originate between 3 to 25 miles (5 to 40 kilometers) belowground, and some extend far deeper.
But which gemstones are found the deepest, and how do they make their way to the surface?
How diamonds form still isn't entirely understood, but laboratory experiments show that the gemstones crystallize only under extreme pressures. Most naturally occurring stones have been traced to the upper mantle, at depths between 93 and 186 miles (150 to 300 km), where pressures can reach beyond 20,000 atmospheres.
Related: What is the rarest mineral on Earth?
For a long time, this put diamonds in competition with a gem called peridot for the title of deepest-occurring gemstone. Peridot is the gem form of a mineral called olivine that makes up more than half of the upper mantle, which extends from the base of the crust down to 255 miles (410 km). But in 2016, scientists described a collection of superdeep diamonds sourced from around 410 miles (660 km), and another batch in 2021 was determined to come from a depth of 466 miles (750 km).
"It'd been hard to tell whether diamonds or peridot were the deepest, but that pretty much settled the debate," Groat said.
To come up with those estimates, researchers studied the diamonds' crystallization patterns as well as their inclusions — bits of mineral or fluids entombed in the gems from when they were formed. Inclusions of a mineral called bridgmanite and iron-nickel-carbon-sulfur melt told scientists that these superdeep diamonds likely formed in the lower mantle, which is made up of about 75% bridgmanite, and that they grew from liquid metal surrounded by methane. At these depths, pressures can exceed 235,000 atmospheres.
Diamonds are also thought to be extremely old. Some estimates suggest that diamonds on the surface today may have formed up to 3.5 billion years ago, although many are much younger. Their longevity is attributed to the strength of their chemical bonds, Groat said. Diamonds are made of carbon, and because they form under pressure, "it takes a great force to break their bonds apart." Heating a diamond above 1,652 degrees Fahrenheit (900 degrees Celsius) will cause it to degrade into graphite.
Gemologists didn't need to burrow into the Earth to learn this; the deepest we've ever penetrated into the planet's interior, at the Kola Superdeep Borehole in Russia, barely scratched the surface, at just 7.8 miles (12.6 km) deep.
Instead, diamonds are brought to the surface by a unique type of magma called kimberlite. Kimberlite magmas tend to be volatile, erupting at speeds of more than 100 feet per second (30 meters per second) and pulling diamonds from the surrounding rocks as they go. In this way, gemstones that formed over billions of years jettison to the surface in months or even hours.
Beyond their aesthetic value and their natural hardness, which makes them attractive to industries interested in blades, drill bits and polishing powders, diamonds contain priceless scientific information, said Ananya Mallik, an experimental petrologist at the University of Arizona. In many cases, "diamonds are the only sources that researchers have for understanding the makeup of the planet's interior and the processes taking place there," she told Live Science.
By studying these gemstones, scientists have learned that early Earth wasn't as tectonically active as it is today. Other analyses have revealed carbon signatures consistent with photosynthesis, showing that the carbon cycle reaches deep into the planet's interior. More recently, scientists studying rare diamonds found evidence of water deeper in the mantle than previously expected, and even discovered entirely new minerals.
"Diamonds have their own value because of their beauty, but in addition to that, their scientific importance makes them even more valuable," Mallik said.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Amanda Heidt is a Utah-based freelance journalist and editor with an omnivorous appetite for anything science, from ecology and biotech to health and history. Her work has appeared in Nature, Science and National Geographic, among other publications, and she was previously an associate editor at The Scientist. Amanda currently serves on the board for the National Association of Science Writers and graduated from Moss Landing Marine Laboratories with a master's degree in marine science and from the University of California, Santa Cruz, with a master's degree in science communication. | Chemistry and Material Sciences |
View Today's Schedule
NASA/CSA/ESA/J. Olmstead (STScI)/N. Madhusudhan (Cambridge University)
Like this week’s post was going to be about anything else! I was way too excited about this to possibly want to expound upon any other topic. I am personally crossing my fingers that this news will wind up being one of the most significant discoveries in the history of humanity—that we just found our first evidence of life on another planet!
For those who don’t have the name “K2-18b” memorized already, the TL;DR is that on September 11 NASA announced that the James Webb Space Telescope may (or may not) have found evidence of life on a planet with that designation. What it found could be only rather interesting, or it could be one of those moments that goes down in science history along with humans walking on the Moon or figuring out the structure of DNA. Let’s take a look at what Webb saw, how the telescope saw it, and what it might mean.
Looking at Planetary Atmospheres
If you happen to think about the James Webb Space Telescope, chances are that what comes to mind are the incredibly lovely images it captures. Personally, I nearly cried when I saw its image of the Pillars of Creation because it was so beautiful (my exact wording when I sent the picture to the Planetarium team was “Webb released the most beautiful picture of space ever taken in the history of telescopes. That’s it, everyone can go home now.”).
But the cameras aren’t the only trick Webb has up its sleeve…er…mirrors. It also has several spectrographs. These are instruments that split light up into its component colors, similar to how sunlight passing through a prism will get broken up into a rainbow—but more complicated than that. All elements and molecules have unique spectrographic signatures. If you look at the spectrum of hydrogen, it will produce a pattern of lines that is unique to hydrogen and completely different from the pattern you will see if you look at helium. This is how astronomers can figure out what something is made from just by looking at the light from it.
At a basic level what Webb did with this exoplanet was look at it when it passed in front of its star. Some of the starlight that reached Webb passed through the planet’s atmosphere to reach the telescope. When Webb passed that light through its spectrographs, the imprint of the molecules and elements of the planet’s atmosphere was there.
K2-18b
Let’s take a moment to meet the planet that might go down in history. It was discovered by the Kepler Space Telescope (RIP you beautiful planet hunter) in 2015 during the second phase of its operation, which was known as K2. This was the 18th planetary system found during that operation, so the star was designated K2-18 and the planet K2-18b (astronomers, while outrageously creative in some fields, are too practical for their own good in others).
The star, K2-18, is a red dwarf, very different from our Sun. It’s under half the Sun’s size and much, much cooler. It can be found about 110 light years away from us in the direction of the constellation Leo. The planet, K2-18b, orbits a mere 13 million miles from the star (which I realize sounds like a big number to us puny humans used to our puny Earth-based distances, but to put it in perspective, Mercury is 29 million miles from the Sun). That is very close for a planet to be to a star, but it’s also a very cool star. That means K2-18b is actually in its sun’s habitable zone—the region around a star where temperatures could be right for liquid water to exist, if all other circumstances allow.
K2-18b is a very different world from Earth. For one thing, it’s a lot bigger, what we in the biz call a super-Earth. It’s twice Earth’s size with over eight times its mass. This is a size of planet that is actually very common out in the cosmos but that we happen to lack in our solar system, which can make studying them both extra-interesting and extra-tricky without a local example to consider.
K2-18b first made headlines in the astronomical community back in 2019, when a team used Hubble to take a look at the atmosphere and found evidence of water vapor. At the time this made K2-18b the smallest world we’d managed to find evidence of water vapor on, and being a rocky, habitable zone planet made the presence of water vapor particularly interesting. All this set it up to be a prime observation candidate for Webb and its massive mirrors.
The Discovery
When Webb looked at the planet’s atmosphere, it actually didn’t detect water vapor, but that doesn’t mean it didn’t find evidence of water. What it did see was plenty of methane and carbon dioxide. The presence of these two gasses without also finding a lot of ammonia suggests something very specific to planetary scientists.
Folks who study exoplanets like to imagine what kind of planets they may one day be able to discover. One such theoretical type of planet was dubbed “Hycean” (for hydrogen-ocean) by a team from Cambridge back in 2021. Such a planet would likely be a super-Earth with an atmosphere rich in hydrogen covering a global ocean. If you had asked me two weeks ago what an atmosphere with methane and carbon dioxide but no ammonia meant, I would have said smelly poison. It’s still that, but apparently it’s also the exact kind of atmospheric signature you’d find on a Hycean planet. K2-18b, therefore, is likely the first Hycean world we’ve ever confirmed, and it’s probable that its surface is covered in water.
On any other day that would be the most incredible piece of news! Webb discovered an ocean world! Since life as we know it needs liquid water to exist, one of the first steps to finding it in non-terrestrial places has been to search for the water. And here was a habitable zone world suspected to be covered in a global ocean! Seriously, that news alone would normally have me pin-balling obnoxiously off the walls of the Planetarium office (have I mentioned that I have very tolerant co-workers?).
But in this case, that’s not the end of what Webb found.
Mixed in with the signatures of methane and carbon dioxide in Webb’s atmosphere was a hint of another molecule: dimethyl sulfide, or DMS. And this was where I got stupidly excited, because we also find DMS on Earth, where it can only be produced by life, mostly by phytoplankton in our oceans. We know of no processes on Earth where DMS can be produced without life. This makes DMS a biosignature—scientific evidence of life.
And we just detected it in the atmosphere of an exoplanet. An exoplanet with a global ocean of liquid water.
Take that in for a moment.
Deep Breath
You might be wondering why astronomers aren’t popping champagne and screaming from rooftops around the world that we just confirmed the presence of life on another planet. Well, it’s because we haven’t. Not yet anyway. My personal god, Carl Sagan, once said that “extraordinary claims require extraordinary evidence”, and the claim of alien life would be one of the most extraordinary ever made. And so far, no one is making it.
Webb may have found evidence of DMS, it was not a strong detection, at least by the standards professional scientists like to use. The team who made the discovery call it “marginal”, and say there’s “a non-negligible chance for DMS being present in the atmosphere”. Suitably cautious language considering the implications of the claim, the fact that the detection was not 100% certain, and the fact that K2-18b’s theoretical ocean could turn out to be hostile to life.
Even so, if you read between the extremely dry and jargon-heavy lines of the discovery paper, you can sense the excitement being determinedly tamped down. Every article I’ve read on the subject from folks in the space news community has been very measured and thoughtful and guarded about how they are covering this news. Most didn’t even mention the DMS detection in the headlines. This is the right and responsible way to do it.
But you know what? This is my blog and we may have just possibly discovered an extraterrestrial biosignature on a water-covered exoplanet, so I’m going to go ahead and scream about it for a while.
What’s Next?
Confirming that DMS signature, obviously! Webb is going to be looking at K2-18b again in another wavelength of infrared light to see if it can get a better view of this molecule. Of course even if we can 100% confirm the presence of DMS in the atmosphere, it would not with complete certainty indicate the presence of life on this world. But it sure would be a very strong suggestion that it’s there, and that would be good enough for me.
It could all turn out to be nothing. Or perhaps we’ve finally answered one of humanity’s oldest questions and discovered that we’re not alone in the universe after all.
Take that in for a moment.
Photo Credits:
1. (cover image) An artist’s illustration of the exoplanet K2-18b with its sun in the background. Credit: NASA/CSA/ESA/J. Olmstead (STScI)/N. Madhusudhan (Cambridge University)
2. The unique spectral patterns produced by hydrogen and helium. Credit: Ranjithsiji”
3. An artist’s illustration of the Kepler Space Telescope. Credit: NASA”
5. A model of the molecule dimethyl sulfide, which Webb found hints of in the atmosphere of the exoplanet K2-18b. Credit: Benjah-bmm27” | Chemistry and Material Sciences |
In just under 14 Earth days, Chandrayaan-3 provided scientists with valuable new data and further inspiration to explore the moon. And the Indian Space Research Organization has shared these initial results with the world.
While the data from Chandrayaan-3's rover, named Pragyan, or "wisdom" in Sanskrit, showed the lunar soil contains expected elements such as iron, titanium, aluminum and calcium, it also showed an unexpected surprise — sulfur.
Planetary scientists like me have known that sulfur exists in lunar rocks and soils, but only at a very low concentration. These new measurements imply there may be a higher sulfur concentration than anticipated.
Pragyan has two instruments that analyze the elemental composition of the soil — an alpha particle X-ray spectrometer and a laser-induced breakdown spectrometer, or LIBS for short. Both of these instruments measured sulfur in the soil near the landing site.
Sulfur in soils near the moon's poles might help astronauts live off the land one day, making these measurements an example of science that enables exploration.
Geology of the moon
There are two main rock types on the moon's surface — dark volcanic rock and brighter highland rock. The brightness difference between these two materials forms the familiar "man in the moon" face or "rabbit picking rice" image to the naked eye.
Scientists measuring lunar rock and soil compositions in labs on Earth have found that materials from the dark volcanic plains tend to have more sulfur than the brighter highlands material.
Sulfur mainly comes from volcanic activity. Rocks deep in the moon contain sulfur, and when these rocks melt, the sulfur becomes part of the magma. When the melted rock nears the surface, most of the sulfur in the magma becomes a gas that is released along with water vapor and carbon dioxide.
Some of the sulfur does stay in the magma and is retained within the rock after it cools. This process explains why sulfur is primarily associated with the moon's dark volcanic rocks.
Chandrayaan-3's measurements of sulfur in soils are the first to occur on the moon. The exact amount of sulfur cannot be determined until the data calibration is completed.
The uncalibrated data collected by the LIBS instrument on Pragyan suggests that the moon's highland soils near the poles might have a higher sulfur concentration than highland soils from the equator and possibly even higher than the dark volcanic soils.
These initial results give planetary scientists like me who study the moon new insights into how it works as a geologic system. But we'll still have to wait and see if the fully calibrated data from the Chandrayaan-3 team confirms an elevated sulfur concentration.
Atmospheric sulfur formation
The measurement of sulfur is interesting to scientists for at least two reasons. First, these findings indicate that the highland soils at the lunar poles could have fundamentally different compositions, compared with highland soils at the lunar equatorial regions. This compositional difference likely comes from the different environmental conditions between the two regions — the poles get less direct sunlight.
Second, these results suggest that there's somehow more sulfur in the polar regions. Sulfur concentrated here could have formed from the exceedingly thin lunar atmosphere.
The polar regions of the moon receive less direct sunlight and, as a result, experience extremely low temperatures compared with the rest of the moon. If the surface temperature falls, below -73 degrees C (-99 degrees F), then sulfur from the lunar atmosphere could collect on the surface in solid form — like frost on a window.
Lunar sulfur as a resource
For long-lasting space missions, many agencies have thought about building some sort of base on the moon. Astronauts and robots could travel from the south pole base to collect, process, store and use naturally occurring materials like sulfur on the moon — a concept called in-situ resource utilization.
In-situ resource utilization means fewer trips back to Earth to get supplies and more time and energy spent exploring. Using sulfur as a resource, astronauts could build solar cells and batteries that use sulfur, mix up sulfur-based fertilizer and make sulfur-based concrete for construction.
For one, sulfur-based concrete hardens and becomes strong within hours rather than weeks, and it's more resistant to wear. It also doesn't require water in the mixture, so astronauts could save their valuable water for drinking, crafting breathable oxygen and making rocket fuel.
While seven missions are currently operating on or around the moon, the lunar south pole region hasn't been studied from the surface before, so Pragyan's new measurements will help planetary scientists understand the geologic history of the moon. It'll also allow lunar scientists like me to ask new questions about how the moon formed and evolved. | Chemistry and Material Sciences |
Approximately 2,200 light-years from where you're sitting lie the Cheerio-shaped remains of a dying star – remnants that form a structure famously known as the Ring Nebula. And on Monday (Aug. 21), scientists announced the James Webb Space Telescope has struck gold once again, earning a rather beautiful new view on this iconic cosmic halo.
"When we first saw the images, we were stunned by the amount of detail in them. The bright ring that gives the nebula its name is composed of about 20,000 individual clumps of dense molecular hydrogen gas, each of them about as massive as the Earth," Roger Wesson of Cardiff University said in a statement.
Not to be confused with one of the JWST's very first images, the Southern Ring Nebula, the Ring Nebula (also known as Messier 57) is considered one of the greatest examples of a planetary nebula we have so far. One might argue, however, that "planetary nebula" is a bit of a misleading term for this light-year-wide spectacle. It has nothing to do with planets, really. Planetary nebulas are basically regions of cosmic gas and dust formed from the outer shells of dying stars, in this case a quite spherical and sun-like one.
"Planetary nebulas were once thought to be simple, round objects with a single dying star at the center. They were named for their fuzzy, planet-like appearance through small telescopes," Wesson said. "Only a few thousand years ago, that star was still a red giant that was shedding most of its mass. As a last farewell, the hot core now ionizes, or heats up, this expelled gas, and the nebula responds with colorful emission of light."
What did the JWST find?
If you're wondering what you're looking at here, first of all, the European Space Agency (ESA) painted a wonderful picture of the angle at which we see the Ring Nebula.
In this new image, we're gazing almost directly down one of the structure's poles, the agency explained, and the brightly colored barrel of material is pointed away from it. Keep in mind that, in reality, this scene is in three dimensions. So at the center of this nebula, which ESA likens to a "distorted doughnut," there's a ton of lower density material packed within. That stuff is also pointed away from us.
In the middle of the whole structure lies a star on its way to its ultimate fate. It will soon become a white dwarf, also known as a corpse star. White dwarfs get that grim name because they represent the final stage of stellar evolution.
While this stellar death process is happening, the dying star sort of seems to be ejecting its outer shells of gas, which is what's causing the vibrant "ring" part of the Ring Nebula seen in the new JWST image.
With its state-of-the-art army of infrared sensors, the JWST managed to obtain images that provide "unprecedented spatial resolution and spectral sensitivity" regarding all that cosmic chaos, according to ESA's statement. What this means is the spaceborne telescope, which sits about a million miles (1.6 million km) from Earth, was able to reveal details about the Ring Nebula's intricate structure that scientists simply haven't parsed before.
For instance, by capturing infrared light wavelengths emitted by the nebula, otherwise known as light wavelengths invisible to the human eye, the JWST unveiled information about the inner ring's filament structure as well as approximately ten concentric "arcs" in outer regions of the phenomenon. Those target-shaped features actually came as a surprise.
"These arcs must have formed about every 280 years as the central star was shedding its outer layers," Wesson said. "When a single star evolves into a planetary nebula, there is no process that we know of that has that kind of time period. Instead, these rings suggest that there must be a companion star in the system, orbiting about as far away from the central star as Pluto does from our sun."
"As the dying star was throwing off its atmosphere, the companion star shaped the outflow and sculpted it," Wesson offered as an explanation, highlighting that "no previous telescope had the sensitivity and the spatial resolution to uncover this subtle effect."
The JWST's superpowers
On that note, these findings nicely emphasize that the promise of this machine, once an ambitious dream, has absolutely been realized.
In a nutshell, the JWST's job is to show us things in the universe illuminated in the infrared region of the electromagnetic spectrum; things far beyond the capacity of our unaided eyes and, actually, beyond some of our most powerful instruments.
"We realized that Webb observations would provide us with invaluable insights, since the Ring Nebula fits nicely in the field of view of Webb’s NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) instruments," Wesson said.
With the JWST, the team was able to notice some "curious spikes" pointing directly away from the central star within the ring. These so-called spikes were apparently only faintly visible in images taken by the Hubble Space Telescope. "We think these could be due to molecules that can form in the shadows of the densest parts of the ring, where they are shielded from the direct, intense radiation from the hot central star," Wesson said.
To get into some more technical aspects of the findings, Wesson explains that the team identified a narrow band of emission coming from some molecules within the ring known as polycyclic aromatic hydrocarbons, or PAHs. PAHs are basically carbon-bearing molecules, but importantly for these new JWST results, they were not expected to form within the nebula studied.
It's also worth noting that this isn't the first time the JWST has pointed its hexagonal gold eyes toward the Ring Nebula. Very recently, the machine imaged this pocket of the universe in high-resolution, and scientists added mesmerizing green and purple filters to create a pretty glorious scene for us to admire.
Such imaging also helped experts learn more about the nebula's intricate details
As for what's next, Wesson says a big question that has risen from these new JWST observations is how a regular old, spherical star managed to form a nebula as ornate as this one. Wesson's theory about the star having a companion object helper seems to be a good one so far – but only time will tell whether that's truly the case. The JWST certainly has its hands full. | Chemistry and Material Sciences |
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
Astronomers have used the James Webb Space Telescope for a fresh perspective of an iconic celestial favorite called the Ring Nebula.
The new image captures never-before-seen details within the colorful nebula, located in the Lyra constellation about 2,600 light-years from Earth.
The structure of the Ring Nebula can be glimpsed through amateur telescopes and has been observed and studied for years.
The planetary nebula, which despite its name has nothing to do with planets, is home to the remnants of a dying star as it releases the bulk of its mass.
Planetary nebulae usually have a rounded structure and were so named because they initially resembled the disks from which planets form when French astronomer Charles Messier discovered the first one in 1764.
“I first saw the Ring Nebula as a kid through just a small telescope. I would never have thought that one day, I would be part of the team that would use the most powerful space telescope ever built, to look at this object,” said astrophysicist Jan Cami, a core member of the JWST Ring Nebula Imaging Project, in a statement. He is a professor of physics and astronomy at the Western University’s Institute for Earth and Space Exploration in London, Ontario.
“Scientifically, I am very interested to learn how a star turns its gaseous envelope into this mixture of simple and complex molecules and dust grains, and these new observations will help us figure that out.”
The nebula was created as a dying star, called a white dwarf, began shedding its outer layers into space, creating a complex structure of glowing rings and expanding clouds of gas.
“The James Webb Space Telescope has provided us with an extraordinary view of the Ring Nebula that we’ve never seen before. The high-resolution images not only showcase the intricate details of the nebula’s expanding shell but also reveal the inner region around the central white dwarf in exquisite clarity,” said Mike Barlow, University College London professor emeritus of physics and astronomy and colead scientist of the JWST Ring Nebula Imaging Project, in a statement.
“We are witnessing the final chapters of a star’s life, a preview of the Sun’s distant future so to speak, and JWST’s observations have opened a new window into understanding these awe-inspiring cosmic events. We can use the Ring Nebula as our laboratory to study how planetary nebulae form and evolve.”
Stellar life history and chemical makeup
The star’s radiation interacts with the elements that have already been released, causing them to glow. Each chemical element creates a specific color, allowing astronomers to study the evolution of the star.
And astronomers still have questions about the different processes that take place within planetary nebulae.
“The structure in this object is incredible, and to think that this is all created by just one dying star,” said astrophysicist Els Peeters, a core member of the JWST Ring Nebula Imaging Project, in a statement. She is a professor of physics and astronomy at Western’s Institute for Earth and Space Exploration.
“Beyond the morphological treasure trove, there is also much information on the chemical makeup of the gas and dust in these observations. We even found large carbonaceous molecules in this object, and we have no clear idea how they got there, yet.” | Chemistry and Material Sciences |
While watching the night sky in 1952, astronomers at Caltech’s Palomar Observatory were baffled when three stars simply vanished from a region of the sky. The vanishing stars, which had been seen as a cluster of three “star-like” points, were there at one point. However, when astronomers looked at the same patch of sky an hour later, the stars had disappeared.
Despite the decades since the 1950s, nobody has ever managed to capture images of those three star-like points ever again. This has, of course, only deepened the mystery surrounding these possible stars. However, a new study may offer some answers to this decades-old conundrum.
Before this study, the main prevailing assumption behind the vanishing stars was that something caused them to dim suddenly, going from a magnitude of 15 to one that is so low the observatory wasn’t able to detect it. However, attempts to locate said stars with more sensitive telescopes have also turned up nothing.
Enter this new study, which posits that there are three possible solutions to the mysterious stars that disappeared that night. The first possible answer is that the three star-like points were actually just a single star magnified into three. This is the most unlikely, as it would rely on us capturing a very rare stellar event, such as a radio burst from a magnetar neutron star, at just the right moment.
The other two possibilities, the researchers outline, is that the three vanishing stars were some other kind of cosmic entity that moved between the two images and has continued to move, making it impossible to tie to the same star-like points astronomers witnessed. The third possibility, of course, is that the stars were really something more Earthbound, like nuclear dust settling from nearby test sites that would have still been active during the 1950s.
The last two explanations for the vanishing stars are the most likely. However, it is impossible to rule out the possibility that those astronomers witnessed some kind of rare cosmic event without realizing it. It certainly wouldn’t be the first time that happened. | Chemistry and Material Sciences |
Did NASA's Viking landers kill Martian life in 1976?In 1976, NASA launched the Viking 1 and Viking 2 landers, which performed four distinct experiments to explore the Martian landscape for signs of life.Rizwan Choudhury| Sep 09, 2023 01:47 PM ESTCreated: Sep 09, 2023 01:47 PM ESTscienceMars.Source: NASA Get a daily digest of the latest news in tech, science, and technology, delivered right to your mailbox. Subscribe now.By subscribing, you agree to our Terms of Use and Policies You may unsubscribe at any time.Astrobiologist Dirk Schulze-Makuch from Technical University Berlin has put forward a controversial argument that NASA's Viking landers could have unintentionally destroyed microbial life on Mars almost 50 years ago. His hypothesis, published in a June 27 article for Big Think, has lately caused a divide amongst experts and reignited debates surrounding the scientific process of searching for life beyond Earth.The Viking missionsIn 1976, NASA launched the Viking 1 and Viking 2 landers, which performed four distinct experiments to explore the Martian landscape for signs of life. These experiments were the gas chromatograph mass spectrometer (GCMS), the labeled release experiment, the pyrolytic release experiment, and the gas exchange experiment. See Also Related Scientists test heating and cooling for moon and Mars on ISS NASA finds Mars days shrinking, cites increase in spin speed Mars Express reveals 'halo' on Olympus Mons — and it's huge Viking lander.Source: NASA Each sought to understand the metabolic, photosynthetic, and respiratory mechanisms that could exist in Martian soil. Yet, the outcomes of these tests have confounded scientists for decades. Some, like the labeled release and pyrolytic release experiments, hinted at metabolic activities, while others, notably the gas exchange experiment, yielded negative results.The water conundrumSchulze-Makuch posits that the Viking landers, designed with an Earth-centric perspective, could have oversaturated the Martian samples with water. On Earth, water is often considered a universal solvent for life; however, on Mars, where conditions are markedly different, too much water might have been detrimental.Schulze-Makuch cites the Atacama Desert in Chile—home to extreme microbes that thrive in arid conditions—as a possible Earthly analog. These organisms flourish in hygroscopic rocks, which absorb minimal atmospheric moisture. Similar rocks are believed to exist on Mars, which led Schulze-Makuch to question whether the Viking landers might have annihilated any potential Martian microbes by drowning them in water.According to him, a lot has changed in the half-century since the Viking missions. More landers and rovers have explored the Martian surface in greater detail, revealing indigenous organic compounds in a chlorinated form. This discovery raises questions about whether these compounds derive from biological processes or abiotic chemical reactions. Contradictory views from the scientific communityAs per Live Science, Alberto Fairén, an astrobiologist at Cornell University and co-author of a 2018 study, supports Schulze-Makuch's theory, stating that excessive water could have spelled the demise of Martian microbes, thereby explaining Viking's inconsistent results.On the other side of the debate, an astrobiologist at NASA's Ames Research Center, Chris McKay, argues that subsequent missions like NASA's Phoenix lander have provided alternate explanations. McKay cites the discovery of perchlorates—a class of chemicals also found on Earth—as sufficient evidence to dismiss any speculation about Martian life.Earlier theories and existing skepticismThis is not the first time experts have debated the possibility of Viking's experiments affecting Martian life. In 2018, researchers posited that heating the soil samples during the experiments could have initiated a chemical reaction, thereby killing any microbes. However, most scientists remain skeptical of these theories, standing by the consensus that Viking did not discover life on Mars.While Schulze-Makuch's claim has been deemed provocative by many, it nonetheless brings to light the significant challenges and implications of searching for life on other planets. Whether the Viking missions did indeed come into contact with—and subsequently destroy—Martian life forms remains a contentious issue, necessitating further investigation and potentially more sophisticated methodologies in future Mars missions.As experts debate the interpretation of decades-old data, the question remains: Could we have been closer to discovering extraterrestrial life than we ever realized, and have we learned enough to avoid repeating the same mistakes? Only time—and perhaps future missions to the Red Planet—will tell.Schulze-Makuch has suggested that we require a new Mars mission that focuses on detecting life to test various hypotheses. This mission should investigate possible habitats on Mars, particularly in the Southern Highlands, where life could exist in salt rocks near the surface. The biggest benefit of this mission is that we may be able to access these rocks without drilling, which would significantly reduce engineering complexity and cost. I am eagerly anticipating the start of this mission. HomeScienceAdd Interesting Engineering to your Google News feed.Add Interesting Engineering to your Google News feed.SHOW COMMENT (1) For You MIT student uses AI to design buildings with less concreteA "lost world" from a billion years ago discoveredHow high heat affects EVs and what you can do about itMaybe you can hear sounds in space after allImproved ICEs or all-in on EVs: which is better for the future?Chinese scientists report gene editing tool better than CRISPRUS I.R.S. to use AI to deal with tax evasion and crimesBees that are trained to detect bombsUsing quantum computing to speed up optimization problemsNew lithium extraction method promises cleaner energy output Job Board | Chemistry and Material Sciences |
There are few places in our solar system more intriguing than Europa.
Beneath its cracked icy shell, NASA and planetary scientists suspect this Jupiter-orbiting moon harbors a giant sea, some 40 to 100 miles deep. Now, new observations from the powerful James Webb Space Telescope show a region on Europa's surface contains carbon dioxide, an important ingredient for life as we know it.
The find isn't nearly evidence of actual life, but it makes the ocean world an even more compelling place to further explore.
"We now think that we have observational evidence that the carbon we see on Europa’s surface came from the ocean. That's not a trivial thing. Carbon is a biologically essential element," Samantha Trumbo, a planetary scientist at Cornell University who analyzed the Webb telescope data, said in a statement. (Nearly one-fifth of the human body is composed of carbon, for example.)
On Europa's cracked surface, the carbon dioxide is most concentrated in a region with a relatively young, irregular surface, dubbed Tara Regio, which means "chaos terrain." The legendary Hubble Space Telescope had previously spotted salt in Tara Regio. "Now we’re seeing that carbon dioxide is heavily concentrated there as well," Trumbo explained. "We think this implies that the carbon probably has its ultimate origin in the internal ocean."
The images below show how Webb, which orbits the sun 1 million miles from Earth, viewed Europa. Scientists used the telescope's Near-Infrared Spectrograph, or NIRSpec, a type of instrument that acts similar to a prism, to find the carbon. A spectrograph splits the light it receives into a rich spectrum of colors, revealing the elements present in a distant object.
The first image on left is an infrared Webb image of the distant moon, while the next three views are from its spectrograph:
Want more science and tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newsletter today.
Europa lies hundreds of millions of miles beyond Earth. But NASA plans to get much closer. In 2024, the space agency plans to launch the Europa Clipper mission, which seeks to "determine whether there are places below the surface of Jupiter’s icy moon, Europa, that could support life," NASA explained. The spacecraft will fly by the moon dozens of times, capturing unprecedented data. In this briny sea, conditions might be suitable for life. Whether it potentially contains some primitive life, however, is another question.
Tweet may have been deleted
The Webb telescope's powerful abilities
The Webb telescope — a scientific collaboration between NASA, the European Space Agency, and the Canadian Space Agency — is designed to peer into the deepest cosmos and reveal new insights about the early universe. But it's also peering at intriguing planets in our galaxy, along with the planets and moons in our solar system.
Want more science and tech news delivered straight to your inbox? Sign up for Mashable's Light Speed newsletter today.
Here's how Webb is achieving unparalleled feats, and likely will for decades:
- Giant mirror: Webb's mirror, which captures light, is over 21 feet across. That's over two and a half times larger than the Hubble Space Telescope's mirror. Capturing more light allows Webb to see more distant, ancient objects. As described above, the telescope is peering at stars and galaxies that formed over 13 billion years ago, just a few hundred million years after the Big Bang.
"We're going to see the very first stars and galaxies that ever formed," Jean Creighton, an astronomer and the director of the Manfred Olson Planetarium at the University of Wisconsin–Milwaukee, told Mashable in 2021.
- Infrared view: Unlike Hubble, which largely views light that's visible to us, Webb is primarily an infrared telescope, meaning it views light in the infrared spectrum. This allows us to see far more of the universe. Infrared has longer wavelengths than visible light, so the light waves more efficiently slip through cosmic clouds; the light doesn't as often collide with and get scattered by these densely packed particles. Ultimately, Webb's infrared eyesight can penetrate places Hubble can't.
"It lifts the veil," said Creighton.
- Peering into distant exoplanets: The Webb telescope carries specialized equipment called spectrometers that will revolutionize our understanding of these far-off worlds. The instruments can decipher what molecules (such as water, carbon dioxide, and methane) exist in the atmospheres of distant exoplanets — be they gas giants or smaller rocky worlds. Webb will look at exoplanets in the Milky Way galaxy. Who knows what we'll find?
"We might learn things we never thought about," Mercedes López-Morales, an exoplanet researcher and astrophysicist at the Center for Astrophysics-Harvard & Smithsonian, told Mashable in 2021.
Already, astronomers have successfully found intriguing chemical reactions on a planet 700 light-years away, and the observatory has started looking at one of the most anticipated places in the cosmos: the rocky, Earth-sized planets of the TRAPPIST solar system.
Topics NASA | Chemistry and Material Sciences |
Researchers have identified buried kimberlite, the rocky home of diamonds, by testing the DNA of microbes in the surface soil.
These 'biological fingerprints' can reveal what minerals are buried tens of metres below the earth's surface without having to drill. The researchers believe it is the first use of modern DNA sequencing of microbial communities in the search for buried minerals.
The research published this week in Nature Communications Earth and Environment represents a new tool for mineral exploration, where a full toolbox could save prospectors time and a lot of money, says co-author Bianca Iulianella Phillips, a doctoral candidate at UBC's department of earth, ocean and atmospheric sciences (EOAS).
The technique adds to the relatively limited number of tools that help find buried ore, including initial scans of the ground and analysis of elements in the overlying rock.
"This technique was born from a necessity to see through the earth with greater sensitivity and resolution, and it has the potential to be used where other techniques aren't working," said Phillips.
When ore interacts with soil, it changes the communities of microbes in the soil. The researchers tested this in the lab, introducing kimberlite to soil microbes and watching how they changed in number and species.
"We took those changed communities of microbes as indicators for the presence of ore materials, or biological fingerprints in the soil of buried mineral deposits," said Phillips.
Using these 'indicator' microbes and their DNA sequences, the team tested the surface soil at an exploration site in the Northwest Territories where kimberlite had previously been confirmed through drilling. They found 59 of the 65 indicators were present in the soil, with 19 present in high numbers directly above the buried ore. They also identified new indicator microbes to add to their set.
Using this set, they tested the surface soil at a second site in the Northwest Territories where they suspected kimberlite was present, and precisely located the topological outline and location of kimberlite buried tens of metres beneath the earth's surface. This showed that indicators from one site could predict the location at another site. In future, exploration teams could build up a database of indicator species and test an unknown site to find out if kimberlite deposits are buried beneath the soil.
The researchers evaluated their technique against another technique known as geochemical analysis, which involves testing elements in the soil to identify the minerals beneath. The microbes were more precise when it came to identifying the location of buried ore.
"Microbes are better geochemists than us, and there are thousands of them," said lead author Dr. Rachel Simister, who conducted the work as a postdoctoral researcher in the UBC department of microbiology and immunology (M&I). "You might run out of elements to sample, but you'll never run out of microbes."
The technique, born from work by a team including Phillips, Dr. Simister, Dr. Sean Crowe and the late professor Peter Winterburn, could catalyze the discovery of new kimberlite deposits. These rocks are known not only as potential stores of diamonds, but also for their ability to capture and store atmospheric carbon.
The technique has potential application across other metallic deposits. The team's ongoing research shows similar results for identifying porphyry copper deposits.
"You could use this technique to find minerals to fuel a green economy," said senior author Dr. Crowe, EOAS and M&I professor and Canada Research Chair in Geomicrobiology. "Copper is the most important critical element that we'll need more of going forward."
Dr. Crowe, along with Dr. Simister and co-author Dr. Craig Hart, co-owns spin-off company Discovery Genomics which provides these sequencing services to the mineral resource sector.
"This is exciting because it's part of a growing recognition of the potential for using microbes at every stage of mining, from finding the minerals, to processing them, to returning sites to their natural states." said Dr. Crowe. "Currently, microbial DNA sequencing requires specific expertise and is comparable in cost to other mineral exploration techniques, but this could change with industry adoption."
Story Source:
Journal Reference:
Cite This Page: | Chemistry and Material Sciences |
Astronomers have been left scratching their heads after new research found that our galaxy could actually be a fifth as heavy as previously thought.
This would appear to suggest that the Milky Way is missing some dark matter — the invisible substance which makes up around 85 per cent of all mass in the universe.
Using data from the Gaia telescope – which created a map of 1.8 billion stars in the Milky Way – researchers estimated the total mass of our galaxy to be just 200 billion times that of the sun.
That is around four to five times lower than previous estimates, which have placed it at between 890 billion and just over one trillion solar masses.
Until now it had also been thought that dark matter was at least six times more abundant than ordinary matter.
LARGE SURVEY OF GAS CLOUDS HELPS ASTRONOMERS STUDY THE MILKY WAY A large-scale survey of the inner galaxy revealed a wide range of structures inside the Milky Way. Scientists from Cardiff University and 50 other institutions around the world created the new 3D survey of the inner Milky Way. The map of clouds will help astronomers study the galaxy Called SEDIGISM (Structure, Excitation and Dynamics of the Inner Galactic Interstellar Medium) - it will allow astronomers to push the boundaries of what we know about the structure of our own galaxy. Dr Ana Duarte Cabral, from Cardiff University said this provides a catalogue of 10,000 clouds of molecular gas. This will allow scientists to probe exactly how the spiral structure of the galaxy affects the life cycle of clouds, their properties, and ultimately the star formation that goes on within them. 'What is most exciting about this survey is that it can really help pin down the global galactic structure of the Milky Way, providing an astounding 3D view of the inner galaxy,' she said. The catalogue was created by measuring the rare isotope of the carbon monoxide molecule, 13CO, using the extremely sensitive 12-metre Atacama Pathfinder Experiment telescope in Chile.
However, the new study suggests the latter could actually account for up to a third of all matter, given that most astronomers agree it equates to the mass of about 600 million suns.
This huge discrepancy has scientists urging caution on the finding, because it 'flies in the face of many previous studies'.
'If our galaxy really has as little mass as this work suggests, one would have to explain why previous works based on different techniques all came up with a higher number,' Professor Andrew Pontzen, of University College London, told the Times.
The discovery could have a profound impact on the understanding of our galaxy's 13-billion-year history because it might suggest the Milky Way has endured fewer collisions with other galaxies than some of its counterparts.
The absolute upper mass limit for the Milky Way is 540 billion, according to the international team of astronomers led by the Paris Observatory.
Study author Dr François Hammer, from the Paris Observatory, said researchers were 'very surprised' by their findings.
She explained how astronomers were able to calculate our galaxy's mass by looking at what is known as its rotation curve.
Essentially, the Milky Way is a spinning spiral of between 100 and 400 billion stars which scientists think is enclosed in a dark matter halo.
The Gaia data, therefore, is a fraction of the total number of stars but it is enough to calculate an accurate rotation curve.
It revealed that the Milky Way's curve is different to other large spiral galaxies because it is not flat.
In the 1970s, one of the major breakthroughs in modern astronomy was that the rotational velocities of other large galaxies were much faster than what would be expected from a so-called Keplerian decline.
This is where stellar speeds begin to drop off in accordance with Kepler's laws because almost all of the galaxy's mass is closer to the galactic center.
The discovery led to the theory that large spiral galaxies must be surrounded by halos of dark matter.
With the Milky Way, however, the rotation curve begins to decrease rapidly on the outskirts of the galaxy's disc.
Stars were found to be orbiting slower than expected 50,000 light-years from its centre, indicating that some of the gravity from dark matter was absent.
The researchers said their findings were 'quite exceptional' and explained that the Milky Way's rotation curved 'could be due to the extraordinarily quiet history of our Galaxy'.
Its last major merger occurred around nine billion years ago, compared to the average of six billion years for other spiral galaxies.
The new study will be published in the journal Astronomy & Astrophysics.
WHAT IS THE EUROPEAN SPACE AGENCY'S GAIA PROBE AND WHAT IS DESIGNED TO DO? Gaia is an ambitious mission to chart a three-dimensional map of our galaxy, the Milky Way, and in the process reveal its composition, formation and evolution. Gaia has been circling the sun nearly a million miles beyond Earth's orbit since its launch by the European Space Agency (ESA) in December 2013. On its journey, the probe has been discreetly snapping pictures of the Milky Way, identifying stars from smaller galaxies long ago swallowed up by our own. Tens of thousands of previously undetected objects are expected to be discovered by Gaia, including asteroids that may one day threaten Earth, planets circling nearby stars, and exploding supernovas. Artist's impression of Gaia mapping the stars of the Milky Way. Gaia maps the position of the Milky Way's stars in a couple of ways. It pinpoints the location of the stars but the probe can also plot their movement, by scanning each star about 70 times Astrophysicists also hope to learn more about the distribution of dark matter, the invisible substance thought to hold the observable universe together. They also plan to test Albert Einstein's general theory of relativity by watching how light is deflected by the sun and its planets. The satellite's billion-pixel camera, the largest ever in space, is so powerful it would be able to gauge the diameter of a human hair at a distance of 621 miles (1,000 km). This means nearby stars have been located with unprecedented accuracy. Gaia maps the position of the Milky Way's stars in a couple of ways. Gaia’s all-sky view of our Milky Way Galaxy and neighbouring galaxies, based on measurements of nearly 1.7 billion stars. The map shows the total brightness and colour of stars observed by the ESA satellite in each portion of the sky between July 2014 and May 2016. Brighter regions indicate denser concentrations of especially bright stars, while darker regions correspond to patches of the sky where fewer bright stars are observed. The colour representation is obtained by combining the total amount of light with the amount of blue and red light recorded by Gaia in each patch of the sky. It pinpoints the location of the stars but the probe can also plot their movement, by scanning each star about 70 times. This is what allows scientists to calculate the distance between Earth and each star, which is a crucial measure. In September 2016, ESA released the first batch of data collected by Gaia, which included information on the brightness and position of over a billion stars. In April 2018, this was expanded to high-precision measurements of almost 1.7 billion stars. | Chemistry and Material Sciences |
Dugway Proving Ground, Utah
A saucer-shaped capsule parachuted down gently in the Utah desert today, after a years-long journey through space. Its cargo is a precious collection of rocks and dust from the asteroid Bennu — the first time NASA has ever brought pieces of this type of celestial object back to Earth.
Over the coming days, NASA will fly the bits of Bennu to the Johnson Space Center in Houston, Texas. There, curators will carefully disassemble the container and begin analysing the chemistry and mineralogy of the pristine samples — which might hold clues to the origins of the Solar System.
“I feel like a kid on Christmas Eve who is just too excited to go to sleep,” says Michelle Thompson, a planetary scientist at Purdue University in West Lafayette, Indiana, and a member of the ‘quick look’ team who will have the first chance to study the rocks.
Space hoover
The material comes from the US$1.2-billion OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) mission, which launched in 2016 and arrived at Bennu in 2018. It spent nearly two years studying the dark-coloured, diamond-shaped asteroid before extending its robotic arm to the rocky surface, blasting it with a puff of gas and collecting the dust and rocks it kicked up. That ‘fist bump’ hoovered up so much material that pieces of rock got jammed in the collection mechanism, allowing some of the smaller pebbles to escape. Watching some of those samples get away was “heart breaking”, says Dante Lauretta, a planetary scientist at the University of Arizona in Tucson who was the first principal investigator of the OSIRIS-REx mission.
Still, the spacecraft managed to collect around 250 grams of rocks and dirt — a large cupful — including several chunks that are at least one centimetre long. It is by far the largest amount of material ever brought back from an asteroid. The Japan Aerospace Exploration Agency (JAXA) had previously collected less than one milligram from the asteroid Itokawa in 2005, and 5.4 grams from the asteroid Ryugu in 2019.
Bringing planetary samples back to Earth allows researchers to use cutting-edge laboratory techniques to study what the rocks are made of. The NASA curation team planned to put the Bennu samples into an atmosphere of pure nitrogen soon after the capsule touched down, to reduce the potential for contamination. That will enable scientists to study the asteroid’s geology and chemistry, preserved all the way back to the formation of the Solar System, more than 4.5 billion years ago. The pristine material hasn’t been altered by passing through Earth’s atmosphere, as happens with meteorites. “The thing that will really be different about this sample is we’ll have that chain of custody of keeping it protected from Earth’s atmosphere,” says Nicole Lunning, the mission’s lead sample curator at the Johnson Space Center.
Precious cargo
Bennu is a carbon-rich asteroid, so the samples might resemble carbon-rich meteorites that have fallen to Earth, Thompson says. The bits collected by OSIRIS-REx probably contain organic compounds — carbon-based molecules found in many meteorites that are the building blocks of many exciting types of chemistry, including those conducive to life. “What I find most fascinating are the nucleobases, the components of the genetic code that make up all life from DNA and RNA,” says Daniel Glavin, the senior scientist for sample return at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. These compounds have been found in meteorites before, but those rocks have not been as pristine as the Bennu samples are expected to be. “We can trust the results, because this stuff is clean,” he says.
NASA curators will work their way through unpacking and studying the dust and pebbles inside OSIRIS-REx’s storage container in the coming weeks. Using nitrogen-filled gloveboxes, technicians will analyse the samples with scanners and other instruments to discern how many rock types were collected, and they will record the samples’ colour, volume and porosity.
The curators will collect up to 100 milligrams for the quick-look team to analyse over the first 72 hours. That initial sample will probably be made up of fine-grained material obtained from the outermost parts of the sample capsule, Thompson says. After that, the team will get a chance to study grains that were picked up by 24 stainless-steel contact pads on the outside of the sample container — which were the first things to actually come into contact with Bennu. It will probably be several weeks before the curators open the heart of the sample container and begin extracting the bulk of the material inside.
Early experiments could include looking at how material that was on the surface of Bennu compares with what came from deeper inside the asteroid, Thompson says. OSIRIS-REx’s robotic arm might have plunged as deep as 40 centimetres under Bennu’s rubbly surface when executing its fist bump.
Work interrupted?
NASA has scheduled a press conference on 11 October to unveil the first scientific results. But its work on the mission could be interrupted if the US government shuts down on 1 October. Republicans and Democrats in Congress have been battling over priorities for funding the federal government in 2024. If the situation remains in a stalemate by the time the US fiscal year ends on 30 September, then federal agencies, including NASA, might close until an agreement can be reached. If that were to happen while the Bennu sample is at NASA, then “certain steps leading to its highly anticipated analysis will possibly be delayed, but the sample will remain protected and safe”, says Lori Glaze, head of NASA’s planetary sciences division. “The sample waited for more than 4 billion years for humans to study it, and if it takes us a little longer, I think we’ll be okay.”
At least 70% of the Bennu material will be saved for scientists outside NASA and for future generations to study. Furthermore, 4% of the sample will go to the Canadian Space Agency, which helped to build a laser instrument aboard OSIRIS-REx, and 0.5% will go to JAXA in exchange for samples of Ryugu, so that researchers can compare the two asteroids.
Meanwhile, the rest of the OSIRIS spacecraft continues to fly through space after dropping off its sample-return capsule. It is headed to study Apophis, an asteroid with a different, ‘stony’, chemical composition that will whizz dramatically close past Earth in 2029. | Chemistry and Material Sciences |
Carbon Capture and Storage projects in Denmark at risk from bitumen formation
Carbon Capture and Storage (CCS) is increasingly being cited to help our global warming crisis by reducing greenhouse gas emissions through capturing carbon dioxide and storing deep underground. In the Danish North Sea, chalk rocks below the sea bed hold depleted oil and gas reserves and are now being considered for storing carbon dioxide to capitalize upon the pre-established infrastructure from the fossil fuel industry.
However, new research published in Marine and Petroleum Geology has considered the potential issues arising from interaction of the stored carbon dioxide with oil and gas (hydrocarbon) residues left in the rock, which can be up to 30% in chalk and 60% in sandstones.
Rasmus Stenshøj from Aarhus University, Denmark, and colleagues at the Energy & Environmental Research Center, U.S., conducted an experiment on a chalk sample of a few centimeters dating to the Upper Cretaceous (66 to ~100 million years ago) from the Halfdan Field of the North Sea.
The researchers recreated the environmental conditions of the rock from the seabed before injecting supercritical carbon dioxide (when it has properties of both a gas and liquid above a certain temperature and pressure) into the rock over a period of nine days. They then used a series of chemical and physical techniques to analyze the hydrocarbons present in rock samples taken before and after supercritical carbon dioxide injection.
Based upon temperature, different forms of hydrocarbons are present: light oil at 0–100°C, mobile oil at 100–200°C, semi-mobile oil at 200–300°C, immobile oil at 300–375°C and bitumen at 375–650°C.
Initial results revealed that the supercritical carbon dioxide caused lighter hydrocarbons to move through the rock, while heavier forms, such as bitumen and asphaltene-rich immobile oil, were left behind. This can cause blockages in the mobilization of the carbon dioxide through the rock and hamper the efficiency of the Carbon Capture and Storage system.
Importantly, the researchers found that the change in pressure at the exit point of the system resulted in more of the bitumen and other heavy hydrocarbon deposits, comprising up to 10.5% of the total rock volume here, whereas before the experiment this was just 4.17%. There is overall a distinct trend in increasing heavy hydrocarbon deposition through the system up to the exit point, thought to result from absorption of hydrocarbons by the supercritical carbon dioxide changing its solubility. Stenshøj and collaborators term this increasing bitumen from inlet to outlet the Avalanche Effect.
Immobile hydrocarbon and bitumen percentages around the inlet before and after injection are somewhat similar, which the researchers state as evidence of the supercritical carbon dioxide mobilizing through the crude oil phase to extract lighter hydrocarbons for removal through the system, leaving behind the heavier bitumen. It is suggested that this results from a direct pushing force of oil from the carbon dioxide, rather than a splitting force.
Analyzing the samples under a microscope prior to injection revealed the pores in the rock contained a mixture of water and oil, but following supercritical carbon dioxide mobilization of oil, the latter was distributed throughout the rock pores replacing water, and even accumulating in the microscopic shells of the ancient fossils of organisms known as foraminifera. This occurs as the oil is drawn into the water-dominated pores by capillary forces, hence the sample became more oil saturated, which led to a change of color to darker brown.
The solubility of hydrocarbons in response to supercritical carbon dioxide is a complex process, which can be affected by changes in temperature, pressure, hydrocarbon content and clays. Clearly the accumulation of heavier hydrocarbons at exit points can lead to plugging of the Carbon Capture and Storage system, impacting its efficiency. With enhanced research into the siting of these storage systems based upon hydrocarbon content, the possibility of making a real difference to global warming remains a tantalizing one.
More information: Rasmus Stenshøj et al, Hydrocarbon residue in a Danish chalk reservoir and its effects on CO2 injectivity, Marine and Petroleum Geology (2023). DOI: 10.1016/j.marpetgeo.2023.106424
© 2023 Science X Network | Chemistry and Material Sciences |
A spectacular fireball just streaked across Melbourne, but astronomers didn't see it coming
The first hours after a fireball sighting are like a detective mystery. Last night around midnight, people across Melbourne took to social media to report sightings of a bright light slowly streaking across the sky.
Video footage clearly shows the fireball break apart, with these fragments in turn burning up, meaning this object was big.
An unexpected piece of space junk
There have been reports across Victoria of a loud explosion. Known as sonic booms, such sounds imply the pieces survived long enough to enter the lower atmosphere—otherwise they wouldn't be audible from the ground. In turn, this tells us at least a part of this fireball was dense.
Additionally, the glow of the fireball had clearly discernible colors, particularly orange, in some videos. This tells us the object isn't a space rock, but is human-made, with a significant amount of plastics or metals burning up (familiar to anyone in high school chemistry class burning materials in the Bunsen burner).
So, it's likely we just witnessed several tons of space junk—anything humans have put into orbit that isn't under our control any longer—re-enter Earth's atmosphere. However, nothing was predicted for reentry on the global space debris tracking site SatView.
According to an early analysis by US-based astronomer Jonathan McDowell, the fireball may have been the third stage of a Soyuz 2 rocket carrying the navigation satellite GLONASS-K2. This was launched by Roscosmos (the Russian space agency) on August 7 from the Plesetsk Cosmodrome about 800km north of Moscow.
The incredible brightness of the fireball is thanks to the tremendous speed at which objects re-enter Earth's thin upper atmosphere, 25,000 kilometers per hour or more.
When you rub your hands together, they get warm from the friction between them. Do that a thousand times faster and you can start to imagine them glowing white hot from the heat. If the friction is between the metal of the space junk and Earth's thin atmosphere at an altitude of 100km, we can get a very bright glow.
You can help astronomers with the details
To help us confirm what the fireball was and where it came from, we need witnesses to download the Fireballs in the Sky App and recreate the passage of that trail as best they can.
From all those sightings we can triangulate the trajectory and determine where any surviving pieces might have landed and try to collect them. Reports so far are conflicting and we need more data. It appears it came into the atmosphere from the north-west across Victoria to Tasmania in the south-east, but it's too soon to tell what its exact path was.
Most space junk doesn't make it to Earth. The incredible heat of 5,000 Kelvin or greater generated by the re-entry burns up almost all such pieces.
Some hardier engine blocks can make it to the ground, however, which is why alerts about space junk re-entering the atmosphere are sent out to aircraft in particular.
However, space junk travels so fast, even a very small mistake in the calculation of the re-entry will have it show up hundreds of kilometers away instead. For most purposes, such warnings are not as helpful as they could be.
To improve this system, we need better tracking stations on the ground and advances in the modeling of the interaction between space junk and the upper atmosphere to improve our forecasts.
Thankfully buildings, let alone people, are tiny targets relative to the vast unpopulated reaches of land and sea. While there have been reported hits, these are thankfully incredibly rare, making space junk hardly a danger for us on Earth.
As astronomers now rush to work out the details of this beautiful fireball, it also marks a spectacular opening for Australia's National Science Week, with thousands of live talks explaining science as widely as possible, just like this event.
Provided by The Conversation | Chemistry and Material Sciences |
When giant impacts brought Earth its precious metals such as gold and platinum long ago, those metals remained near our planet's surface thanks to a molten magma ocean. This ocean, formed by the impact itself, was able to trap the metals and keep them safe.
The gold in our jewelry, the platinum in our computer electronics, the iridium in our OLEDs (organic LEDs) — all of it — has had a long and tumultuous journey. These elements originally formed from the mergers of neutron stars that resulted in violent kilonova explosions. Then, they seeded the giant molecular cloud of star-forming gas and dust that eventually formed our solar system billions of years ago.
When Earth formed, these precious metals were included in its structure, too. They’re specifically called highly siderophile elements, or HSEs, which means they are strongly attracted to iron. Besides gold, iridium and platinum, the other HSEs are osmium, palladium, rhenium, rhodium and ruthenium.
There are large amounts of those precious metals from the ancient solar system locked up within the dense iron of Earth’s core; so you might assume that any precious metals delivered by later impacts should have also sunk to the core. Fortunately for us, they didn’t.
But how did the precious metals that are so valuable to us today stay near the Earth’s surface?
Geophysicists have struggled with this question for decades, and now Jun Korenaga, who is a professor of geophysics at Yale University,and Simone Marchi, a planetary scientist at the Southwest Research Institute in Colorado may have an answer at last.
After the bulk of Earth formed, it was slammed into several times by rogue protoplanets. One such collision with a Mars-sized object, known as Theia, resulted in debris that formed Earth’s Moon. Most of Theia, and the other protoplanets, were subsumed by the growing Earth, however. These protoplanets also contained precious metals, but rather than sink through Earth’s core where they could join the iron, the HSEs became trapped within Earth’s mantle, which allowed them easy access to the surface.
This was all previously known, but nobody knew how the metals were trapped — until now, thanks to computer models run by Korenaga and Marchi.
"Our research is a good example of making an unexpected discovery after re-examining conventional wisdom," said Korenaga in a statement.
Their model shows how, after each giant impact very early in the young Earth’s history, a huge ocean of magma formed within Earth’s lithosphere, which describes the crust and upper mantle. The precious metals begin sinking through this ocean until they reached a partially molten transition layer. This slowed the metals' descent, allowing the lower mantle to cool and solidify before the HSEs could percolate through it to the core. Trapped in the mantle, the HSEs were then subject to convection from thermal currents emanating from Earth’s hot core, which to this day continue to move the precious metals around the Earth and bring them to the surface.
"This transient region almost always forms when a big impactor hits the early Earth, making our theory quite robust," said Marchi.
While this all took place some 4.5 billion years ago, echoes of these impacts and the resulting transition regions still remain, in the form of two "large low-shear-velocity provinces," or LLSVPs that appear as geophysical anomalies in the deep mantle beneath Africa and the Pacific Ocean. When geophysicists describe the LLSVPs as large, they’re not kidding: they make up as much as 9% of Earth’s volume, stretching thousands of kilometers laterally and more than 1,000 kilometers vertically from the mantle’s boundary with the core.
The findings were published on Oct. 9 in the journal Proceedings of the National Academy of Sciences. | Chemistry and Material Sciences |
Nasa's Osiris-Rex capsule will come screaming into Earth's atmosphere on Sunday at more than 15 times the speed of a rifle bullet.
It will make a fireball in the sky as it does so, but a heat shield and parachutes will slow the descent and bring it into a gentle touchdown in Utah's West Desert.
The capsule caries a precious cargo - a handful of dust grabbed from asteroid Bennu, a mountain-sized space rock that promises to inform the most profound of questions: Where do we come from?
"When we get the 250g (9oz) of asteroid Bennu back on Earth, we'll be looking at material that existed before our planet, maybe even some grains that existed before our Solar System," says Prof Dante Lauretta, the principal investigator on the mission.
"We're trying to piece together our beginnings. How did the Earth form and why is it a habitable world? Where did the oceans get their water; where did the air in our atmosphere come from; and most importantly, what is the source of the organic molecules that make up all life on Earth?"
The prevailing thinking is that many of the key components were actually delivered to our planet early in its history in a rain of impacting asteroids, many of them perhaps just like Bennu.
Engineers have commanded the final adjustments to the Osiris-Rex spacecraft's trajectory. All that remains is to make the "go, no-go" decision to release the capsule to fall to Earth this weekend.
The quest to acquire fragments of Bennu began in 2016, when Nasa launched the Osiris-Rex probe towards the 500m (1,640ft) wide object. It took two years to reach the body and a further two years of mapping before the mission team could confidently identify a location on the space rock's surface to scoop up a "soil" sample.
Key to that choice was the British rock legend and astrophysicist Dr Sir Brian May. The Queen guitarist is an expert in stereo imaging.
He has the ability to align two pictures of a subject taken from slightly different angles to give a sense of perspective - making a 3D view of a scene. He and collaborator Claudia Manzoni did this for the shortlist of possible sample sites on Bennu. They established the safest places to approach.
"I always say you need art as well as science," Sir Brian told BBC News. "You need to feel the terrain to know if the spaceship is likely to fall over or if it will hit this 'rock of doom' that was right on the edge of the eventual chosen site, called Nightingale. If that had happened it would have been disastrous."
The moment of sample capture, on 20 October 2020, was astonishing.
Osiris-Rex lowered itself down to the asteroid - holding its grabbing mechanism on the end of a 3m-long (10ft) boom.
The idea was to slap the surface and, at the same time, give out a blast of nitrogen gas to kick up gravel and dust. What happened next was something of a shock.
When the mechanism made contact, the surface parted like a fluid. By the time the gas fired, the disc was 10cm (4in) down. The nitrogen pressure blasted a crater 8m (26ft) in diameter. Material flew in all directions, but crucially also into the collection chamber.
And so now here we are. Osiris-Rex is just hours away from delivering the Bennu sample at the end of what has been a seven-year, seven-billion-kilometre round trip.
Once the capsule is safely on the ground, it will be whisked off to the Johnson Space Center in Texas, where a dedicated cleanroom has been built to analyse the samples.
Dr Ashley King from London's Natural History Museum (NHM) will be one of the very first scientists to get his gloves on the material. He is part of the "quick look" team that will do the initial analysis.
"Bringing back samples from an asteroid - we don't do that very often. So you want to do those first measurements, and you want to do them really well," he says. "It's incredibly exciting."
Nasa regards Bennu as the most dangerous rock in the Solar System. Its path through space gives it the highest probability of impacting Earth of any known asteroid. But don't panic, the odds are very low - akin to tossing a coin and getting 11 heads in a row. And any impact isn't likely until late next century.
Bennu probably contains a lot of water - as much as 10% by weight - bound up in its minerals. Scientists will be looking to see if the ratio of different types of hydrogen atoms in this water is similar to that in Earth's oceans.
If, as some experts believe, the early Earth was so hot that it lost much of its water, then finding an HâO match with Bennu would bolster the idea that later bombardment from asteroids was important in providing volume for our oceans.
Bennu probably also contains about 5-10% by weight of carbon. This is where a lot of the interest lies. As we know, life on our planet is based on organic chemistry. As well as water, did complex molecules have to be delivered from space to kickstart biology on the young Earth?
"One of the very first analyses to be done on the sample will include an inventory of all of the carbon-based molecules that it contains," says the NHM's Prof Sara Russell.
"We know from looking at meteorites that asteroids are likely to contain a zoo of different organic molecules. But in meteorites, they're often very contaminated, and so this sample return gives us a chance to really find out what the pristine organic components of Bennu are."
Prof Lauretta adds: "We've actually never looked for the amino acids that are used in proteins in meteorites because of this contamination issue. So we think we're really going to advance our understanding of what we call the exogenous delivery hypothesis, the idea that these asteroids were the source of the building blocks of life."
Additional reporting by Rebecca Morelle, Alison Francis and Kevin Church
Sign up for our morning newsletter and get BBC News in your inbox. | Chemistry and Material Sciences |
Planetary scientists want to search for biosignatures in what they believe was once a Martian mud lake.
After scientists carefully studied what they believe are desiccated remnants of an equatorial mud lake on Mars, their study of Hydraotes Chaos suggests a buried trove of water surged onto the surface. If researchers are right, then this flat could become prime ground for future missions seeking traces of life on Mars.
"While Martian lakes and mud volcanoes have been subjects of prior studies, our work represents the first comprehensive analysis specifically focused on a putative mud lake," Alexis Rodriguez, a senior scientist at the Planetary Science Institute in Arizona, told Space.com.
More generally, scientists suggest surface water on Mars froze over about 3.7 billion years ago as the atmosphere thinned and the surface cooled. But underground, groundwater might still have remained liquid in vast chambers. Moreover, life forms might have abided in those catacombs — leaving behind traces of their existence.
Only around 3.4 billion years ago did that system of aquifers break down in Hydraotes Chaos, triggering floods of epic proportions that dumped mountains' worth of sediment onto the surface, the study suggests. Future close-up missions could someday examine that sediment for biosignatures.
Hydraotes Chaos is an example of geography called chaos terrain: a jumble of jutting mountains, broken craters, and jagged vales. Rodriguez and colleagues pored over images of Hydraotes Chaos taken by NASA's Mars Reconnaissance Orbiter in search of more clues.
In the midst of the chaos terrain's maelstrom lies a calm circle of relatively flat ground. This plain is pockmarked with cones and domes, with hints of mud bubbling from below — suggesting that sediment did not arrive via a rushing flash flood, but instead rose from underneath.
Based on simulations, the authors suggest Hydraotes Chaos overlaid a reservoir of buried biosignature-rich water—potentially in the form of thick ice sheets.
Ultimately — potentially from the Red Planet's internal heat melting the ice — that water bubbled up to the surface and created a muddy lake. As the water dissipated, it would have left behind all those tantalizing biosignatures.
Curiously, that water might have remained underground even after those megafloods. In fact, the authors' results suggest the sediment on the surface of this mud lake dates from only around 1.1 billion years ago: long after most of Mars's groundwater ought to have flooded out, and certainly long after Mars was habitable.
With that timeline in mind, Rodriguez and colleagues plan to analyze what lies under the surface of the lake. That, Rodriguez tells Space.com, would allow scientists to establish when in Martian history the planet might have hosted life.
Scientists might even be able to take future research right into the ancient mud. NASA’s Ames Research Center is working on an instrument called Extractor for
Chemical Analysis of Lipid Biomarkers in Regolith (EXCALIBR) that would test extraterrestrial rocks for biomarkers: in particular, lipids. A future NASA mission might take EXCALIBR with it to the moon or Mars. "Hydraotes Chaos is under consideration as a candidate landing site for [EXCALIBR]," Rodriguez told Space.com.
This research is described in a paper published Wednesday (Oct. 18) in the journal Nature Scientific Reports. | Chemistry and Material Sciences |
A new sounding rocket mission is headed to space to understand how explosive stellar deaths lay the groundwork for new star systems. The Integral Field Ultraviolet Spectroscopic Experiment, or INFUSE, sounding rocket mission, will launch from the White Sands Missile Range in New Mexico on Oct. 29, 2023, at 9:35 p.m. MDT.
For a few months each year, the constellation Cygnus (Latin for “swan”) swoops through the northern hemisphere’s night sky. Just above its wing is a favorite target for backyard astronomers and professional scientists alike: the Cygnus Loop, also known as the Veil Nebula.
The Cygnus Loop is the remnant of a star that was once 20 times the size of our Sun. Some 20,000 years ago, that star collapsed under its own gravity and erupted into a supernova. Even from 2,600 light-years away, astronomers estimate the flash of light would have been bright enough to see from Earth during the day.
Supernovae are part of a great life cycle. They spray heavy metals forged in a star’s core into the clouds of surrounding dust and gas. They are the source of all chemical elements in our universe heavier than iron, including those that make up our own bodies. From the churned-up clouds and star stuff left in their wake, gases and dust from supernovae gradually clump together to form planets, stars, and new star systems.
“Supernovae like the one that created the Cygnus Loop have a huge impact on how galaxies form,” said Brian Fleming, a research professor at the University of Colorado Boulder and principal investigator for the INFUSE mission.
The Cygnus Loop provides a rare look at a supernova blast still in progress. Already over 120 light-years across, the massive cloud is still expanding today at approximately 930,000 miles per hour (about 1.5 million kilometers per hour).
What our telescopes capture from the Cygnus Loop is not the supernova blast itself. Instead, we see the dust and gas superheated by the shock front, which glows as it cools back down.
“INFUSE will observe how the supernova dumps energy into the Milky Way by catching light given off just as the blast wave crashes into pockets of cold gas floating around the galaxy,” Fleming said.
To see that shock front at its sizzling edge, Fleming and his team have developed a telescope that measures far-ultraviolet light – a kind of light too energetic for our eyes to see. This light reveals gas at temperatures between 90,000 and 540,000 degrees Fahrenheit (about 50,000 to 300,000 degrees Celsius) that is still sizzling after impact.
INFUSE is an integral field spectrograph, the first instrument of its kind to fly to space. The instrument combines the strengths of two ways of studying light: imaging and spectroscopy. Your typical telescopes have cameras that excel at creating images – showing where light is coming from, faithfully revealing its spatial arrangement. But telescopes don’t separate light into different wavelengths or “colors” – instead, all of the different wavelengths overlap one another in the resulting image.
Spectroscopy, on the other hand, takes a single beam of light and separates it into its component wavelengths or spectrum, much as a prism separates light into a rainbow. This procedure reveals all kinds of information about what the light source is made of, its temperature, and how it is moving. But spectroscopy can only look at a single sliver of light at a time. It’s like looking at the night sky through a narrow keyhole.
The INFUSE instrument captures an image and then “slices” it up, lining up the slices into one giant “keyhole.” The spectrometer can then spread each of the slices into its spectrum. This data can be reassembled into a 3-dimensional image that scientists call a “data cube” – like a stack of images where each layer reveals a specific wavelength of light.
Using the data from INFUSE, Fleming and his team will not only identify specific elements and their temperatures, but they’ll also see where those different elements lie along the shock front.
“It’s a very exciting project to be a part of,” said lead graduate student Emily Witt, also at CU Boulder, who led most of the assembly and testing of INFUSE and will lead the data analysis. “With these first-of-their-kind measurements, we will better understand how these elements from the supernova mix with the environment around them. It’s a big step toward understanding how material from supernovas becomes part of planets like Earth and even people like us.”
To get to space, the INFUSE payload will fly aboard a sounding rocket. These nimble, crewless rockets launch into space for a few minutes of data collection before falling back to the ground. The INFUSE payload will fly aboard a two-stage Black Brant 9 sounding rocket, aiming for a peak altitude of about 150 miles (240 kilometers), where it will make its observations, before parachuting back to the ground to be recovered. The team hopes to upgrade the instrument and launch again. In fact, parts of the INFUSE rocket are themselves repurposed from the DEUCE mission, which launched from Australia in 2022.
NASA's Sounding Rocket Program is conducted at the agency's Wallops Flight Facility at Wallops Island, Virginia, which is managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. NASA's Heliophysics Division manages the sounding rocket program for the agency. The development of the INFUSE payload was supported by NASA’s Astrophysics Division. | Chemistry and Material Sciences |
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
Scientists have detected a surprising amount of a rare version of helium, called helium-3, in volcanic rocks on Canada’s Baffin Island, lending support to the theory that the noble gas is leaking from Earth’s core — and has been for millennia.
The research team also detected helium-4 within the rocks.
While helium-4 is common on Earth, helium-3 is more readily found elsewhere in the cosmos, which is why scientists were surprised to detect a larger amount of the element than had been previously reported from the rocks on Baffin Island. A study describing the discovery published recently in the journal Nature.
“At the most basic level, there is little 3He (helium-3) in the universe compared to 4He (helium-4),” said lead study author Forrest Horton, associate scientist in the department of geology and geophysics at Woods Hole Oceanographic Institution, in an email.
“3He is rare in Earth because it has not been produced in or added to the planet in significant quantities and it is lost to space,” Horton added. “As Earth’s rocky portion stirs and convects like hot water on a stove top, material ascends, cools, and sinks.
During the cooling stage, helium is lost to the atmosphere and then to space.”
Detecting elements that leak from Earth’s core can help scientists unlock insights into how our planet formed and evolved over time, and the new findings provide evidence to bolster an existing hypothesis about how our planet came to be.
A trove of ‘scientific treasures’
Baffin Island, located in the territory of Nunavut, is the largest island in Canada. It’s also the fifth-largest island in the world.
A high ratio of helium-3 to helium-4 was first detected in Baffin Island volcanic rocks by Solveigh Lass-Evans as part of her doctoral studies under the supervision of University of Edinburgh scientist Finlay Stuart. Their findings were published in Nature in 2003.
The composition of a planet is a reflection of the elements that formed it, and previous research found that trace amounts of helium-3 leaking from Earth’s core supports the popular theory that our planet originated in a solar nebula — a cloud of gas and dust that likely collapsed due to the shock wave of a nearby supernova — which contained the element.
Horton and his colleagues took it a step further when they conducted research on Baffin Island in 2018, studying the lava that erupted millions of years ago when Greenland and North America split apart, making way for a new seafloor. They wanted to investigate the rocks that may contain insights about the contents locked within Earth’s core and mantle, the mostly solid layer of Earth’s interior located beneath its surface.
The researchers traveled by helicopter to reach the remote, otherworldly landscape of the island, where lava flows have formed towering cliffs, giant icebergs float by and polar bears stalk the coastline. Local organizations, including the Qikiqtani Inuit Association and Nunavut Research Institute, provided the researchers with access, advice and protection from the bears, Horton said.
“This area on Baffin Island holds special importance both as sacred lands for the local communities and as a scientific window into the deep Earth,” he said.
The Arctic rocks that Horton and his team investigated revealed surprisingly higher measurements of helium-3 and helium-4 than was reported by previous research, and the measurements varied among the samples they collected.
“Many of the lavas are full of bright green olivine (also known as the gemstone peridot), so breaking off fresh pieces with a rock hammer was as thrilling as breaking apart geodes as a kid: each rock was a treasure to be discovered,” Horton said. “And what scientific treasures they turned out to be!”
Only about one helium-3 atom exists for every million helium-4 atoms, Horton said. The team measured about 10 million helium-3 atoms per gram of olivine crystals.
“Our high 3He/4He measurements imply that gases, presumably inherited from the solar nebula during solar system formation, are better preserved in Earth than previously thought,” he said.
Tracing Earth’s history
But how did the helium-3 end up in the rocks in the first place?
The answer may begin as far back as the big bang, which, when it created the universe, also released an abundance of hydrogen and helium. These elements were incorporated into the formation of galaxies over time.
Scientists believe our solar system formed 4.5 billion years ago within a solar nebula. As the dust cloud collapsed in a supernova, the resulting material formed a spinning disk that eventually gave rise to our sun and the planets, according to NASA.
Helium inherited from the solar nebula likely became locked in Earth’s core as the planet formed, making the core a reservoir of noble gases. As helium-3 leaked from the core, it ascended to the surface through the mantle in the form of magma plumes that eventually erupted on Baffin Island.
“During the eruption, the vast majority of the gases in the magma escaped to the atmosphere,” Horton said. “Only the olivine crystals that grew prior to eruption trapped and preserved the helium from the deep Earth.”
The new research supports the idea that helium-3 is leaking from Earth’s core and has been for some time, but the researchers aren’t entirely sure when this process began.
“The lavas are about 60 million years old, and the ascent of the mantle plume took perhaps tens of millions of years,” Horton said. “So, the helium we measured in these rocks would have escaped the core perhaps 100 million years ago or possibly much earlier.”
Helium leaking from Earth’s core doesn’t affect our planet or have any negative implications, he said. The noble gas does not chemically react with matter, so it won’t have an impact on humanity or the environment.
Next, the research team wants to investigate whether the core is a storehouse of other light elements, which could account for the why Earth’s outer core is less dense than expected.
“Is the core a major repository of elements like carbon and hydrogen, which are so important in terms of planetary habitability? If so, have fluxes of these elements from the core over (Earth’s) history influenced planetary evolution? I am excited to investigate links between helium and other light elements,” Horton said. “Perhaps helium can be used to track other elements across the core-mantle boundary.” | Chemistry and Material Sciences |
Astronomers have uncovered a star that appears on course to become one of the strongest magnets in the universe.
HD 45166 is 3,000 light years away and was spotted with multiple telescopes dotted all over the Earth, not that it's particularly inconspicuous.
Rich in helium, this interstellar behemoth is a few times bigger than our sun.
But experts are more interested in what awaits it after death, when they believe it will become a magnetar.
These super-dense dead stars boast ultra-strong magnetic fields - the most powerful in existence.
While they are found all over our galaxy, astronomers are unsure how they form and hope that finding a likely future candidate will shed more light on their origins.
Based on the data collected from various telescopes, HD 45166 has a magnetic field of 43,000 gauss, which makes it the most magnetic massive star ever found.
The image at the top of this article, an artist's impression of the star, shows it being enveloped by intense winds of particles that are trapped by its magnetic field.
HD 45166 is a binary system and in the background on the left is its companion, a normal blue star in its orbit.
Star's power is immense - and there's much more to come
Lead author, Tomer Shenar of the University of Amsterdam, said the "exciting" discovery was the first of its kind.
Co-author Pablo Marchant said its entire surface "is as magnetic as the strongest human-made magnets".
And yet magnetars are at least a billion times stronger still.
Should HD 45166 indeed be on course to become one, death will see it collapse under its own gravity and become an extremely compact neutron star with a magnetic field of around 100 trillion gauss.
Put it this way: if a magnetar appeared around the same distance as the moon, it would be strong enough to wipe the data from every credit card on Earth.
Read more:
Is this the 'holy grail' of physics?
Pictures of meteor shower from around world
At the moment, there are only 31 known magnetars in the universe, though astronomers suspect there are millions of inactive ones waiting to be found.
Professor Shenar said HD 45166's potential had "been hiding in plain sight all along".
The findings have been published in the journal Science. | Chemistry and Material Sciences |
A planet that suffers scorching 475°C (900°F) temperatures beneath a thick acidic atmosphere may be the last place you'd expect alien life in our Solar System.
But one NASA scientist claims that extraterrestrials are most likely hiding on Venus amid conditions that are unbearable for humans.
The new theory was put forward by Dr Michelle Thaller, a research scientist at the US-based Goddard Space Flight Centre.
She says that 'possible signs of life' have already been seen within the carbon-dioxide filled atmosphere, adding that she was absolutely certain that life exists somewhere.
'We see possible signs of life in the atmosphere of Venus,' Dr Thaller said in an interview with The Sun.
'I never expected Venus. Venus is now one where we see something in the atmosphere that looks very much like it could be produced by bacteria.'
Venus is often described as 'Earth's twin' due to its similar size and structure.
But their conditions couldn't be further apart, as astronomers believe it would be impossible for humans to exist on Venus.
Positioned 67 million miles from the Sun, Venus is the hottest planet in our solar system, suffering temperatures that can even melt lead.
Its atmosphere - comprised of sulfuric acid and carbon dioxide - also adds to the situation, sparking a 'runaway greenhouse effect' that prevents heat from escaping to the space beyond.
Despite this, scientists have long debated whether Venus' clouds may host microbial lifeforms that can survive off sulfur, methane and iron.
Many theorise that photosynthesis is possible on the planet's surface as Venus receives enough solar energy to penetrate through its thick clouds.
However, Professor Dominic Papineau, an astrobiologist at the University College of London, believes Dr Thaller's views are 'difficult to realistically hypothesise'.
Speaking to MailOnline, he explained: 'For life-related chemical reactions to take place, liquid water is necessary. Hence, to find extraterrestrial life, we need to find liquid water, and to find extraterrestrial fossils requires looking for sedimentary rocks that were associated with liquid water in the past.
'This make life on Venus today difficult to realistically hypothesise, because its surface is too hot, although Venus might have had liquid water in its past.
'A problem with a possible fossil record on Venus however is the widespread volcanism that appears to have covered most of the surface in the last few hundreds of millions of years.'
Even still, both Professor Papineau and Dr Thaller agree that the icy moons of our solar system could also be sites of potential microbial life.
NASA suggests there are 290 'traditional Moons' in our solar system - excluding 462 smaller asteroids and minor planets.
'More likely we could find extraterrestrial life and/or fossil on Mars and in the icy moons of the outer solar system,' Professor Papineau continued.
'This is because liquid water exists on those planetary bodies, including within ice at the Martian south pole. Mars and icy moons also have a geological record that might preserve fossils.' | Chemistry and Material Sciences |
Data collected by NASA’s Juno mission indicates a briny past may be bubbling to the surface on Jupiter’s largest moon.
NASA’s Juno mission has observed mineral salts and organic compounds on the surface of Jupiter’s moon Ganymede. Data for this discovery was collected by the Jovian InfraRed Auroral Mapper (JIRAM) spectrometer aboard the spacecraft during a close flyby of the icy moon. The findings, which could help scientists better understand the origin of Ganymede and the composition of its deep ocean, were published on Oct. 30 in the journal Nature Astronomy.
Larger than the planet Mercury, Ganymede is the biggest of Jupiter’s moons and has long been of great interest to scientists due to the vast internal ocean of water hidden beneath its icy crust. Previous spectroscopic observations by NASA’s Galileo spacecraft and Hubble Space Telescope as well as the European Southern Observatory’s Very Large Telescope hinted at the presence of salts and organics, but the spatial resolution of those observations was too low to make a determination.
On June 7, 2021, Juno flew over Ganymede at a minimum altitude of 650 miles (1,046 kilometers). Shortly after the time of closest approach, the JIRAM instrument acquired infrared images and infrared spectra (essentially the chemical fingerprints of materials, based on how they reflect light) of the moon’s surface. Built by the Italian Space Agency, Agenzia Spaziale Italiana, JIRAM was designed to capture the infrared light (invisible to the naked eye) that emerges from deep inside Jupiter, probing the weather layer down to 30 to 45 miles (50 to 70 kilometers) below the gas giant’s cloud tops. But the instrument has also been used to offer insights into the terrain of moons Io, Europa, Ganymede, and Callisto (known collectively as the Galilean moons for their discoverer, Galileo).
The JIRAM data of Ganymede obtained during the flyby achieved an unprecedented spatial resolution for infrared spectroscopy – better than 0.62 miles (1 kilometer) per pixel. With it, Juno scientists were able to detect and analyze the unique spectral features of non-water-ice materials, including hydrated sodium chloride, ammonium chloride, sodium bicarbonate, and possibly aliphatic aldehydes.
“The presence of ammoniated salts suggests that Ganymede may have accumulated materials cold enough to condense ammonia during its formation,” said Federico Tosi, a Juno co-investigator from Italy’s National Institute for Astrophysics in Rome and lead author of the paper. “The carbonate salts could be remnants of carbon dioxide-rich ices.”
Exploring Other Jovian Worlds
Previous modeling of Ganymede’s magnetic field determined the moon’s equatorial region, up to a latitude of about 40 degrees, is shielded from the energetic electron and heavy ion bombardment created by Jupiter’s hellish magnetic field. The presence of such particle fluxes is well known to negatively impact salts and organics.
During the June 2021 flyby, JIRAM covered a narrow range of latitudes (10 degrees north to 30 degrees north) and a broader range of longitudes (minus 35 degrees east to 40 degrees east) in the Jupiter-facing hemisphere.
“We found the greatest abundance of salts and organics in the dark and bright terrains at latitudes protected by the magnetic field,” said Scott Bolton, Juno’s principal investigator from the Southwest Research Institute in San Antonio. “This suggests we are seeing the remnants of a deep ocean brine that reached the surface of this frozen world.”
Ganymede is not the only Jovian world Juno has flown by. The moon Europa, thought to harbor an ocean under its icy crust, also came under Juno’s gaze, first in October 2021 and then in September 2022. Now Io is receiving the flyby treatment. The next close approach to that volcano-festooned world is scheduled for Dec. 30, when the spacecraft will come within 932 miles (1,500 kilometers) of Io’s surface.
More About the Mission
NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Juno mission for the principal investigator, Scott Bolton, of the Southwest Research Institute in San Antonio. Juno is part of NASA’s New Frontiers Program, which is managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. The Italian Space Agency (ASI) funded the Jovian InfraRed Auroral Mapper. Lockheed Martin Space in Denver built and operates the spacecraft.
More information about Juno is available at:
News Media Contacts
DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
[email protected]
Deb Schmid
Southwest Research Institute, San Antonio
210-522-2254
[email protected]
Marco Galliani
National Institute for Astrophysics
+39 06 355 33 390
[email protected]
2023-157 | Chemistry and Material Sciences |
In the swirling ring of asteroids between Mars and Jupiter, one space rock has attracted far more attention than any other.
It's known as 16 Psyche.
The metal-rich asteroid has made headlines because scientists once estimated, if mined, it could be worth way more than all the cash on Earth today.
But the metal that gives 16 Psyche such an eye-popping valuation is interesting to scientists for other reasons.
The dense little world can provide a window into what was happening during the earliest epoch of our Solar System.
Michael Shepard, geoscientist at Bloomsburg University of Pennsylvania, has a special interest in the asteroid and has helped produce 3D models of the rock.
"Psyche will add a big missing piece in our understanding of how the Solar System formed," he said.
The upcoming Psyche mission, led by NASA's Jet Propulsion Laboratory in Southern California, is designed to get up close and personal with 16 Psyche and examine its mysterious exterior.
Building on years of Earth-based observations, scientists hope to reveal exactly what 16 Psyche is: The remnant core of a failed planet? A tiny planet that was crashed into and reassembled? Or a cosmic body shaped by something more exotic, like iron-spewing volcanoes?
With Psyche, those questions could finally be answered.
What's Psyche?
Psyche can refer to three things, making it a little confusing.
It starts with 16 Psyche, the official name of the asteroid that was discovered in 1852 by Italian astronomer Annibale de Gasparis. It's named after the goddess of the soul in Greek mythology.
The "16" denotes that the rock was the 16th minor planetary body discovered. Most of the time, scientists just call it Psyche.
Next, there's the Psyche mission, which consists of a NASA-built orbiter that's also named Psyche.
The mission was selected as part of NASA's Discovery program in 2017.
When it reaches orbit around Psyche, it will be the first time that humans have visited a metal asteroid.
When is NASA launching the Psyche mission?
Psyche's launch window was intended to open on October 5 but NASA delayed the launch by a week, to October 12, to allow more time to fine-tune the spacecraft's thrusters.
The potential launch time is 1:38am AEDT every day. If the window is missed because of weather or other factors, it gets pushed to the following day.
The spacecraft will be launched from the Kennedy Space Center in Florida, aboard a SpaceX Falcon Heavy, one of the world's most powerful rockets.
The mission was originally scheduled to launch in September 2022 and arrive at Psyche in 2026. However, mission development and workforce issues forced NASA to postpone and re-evaluate the timeline.
The mission has now been given the green light to continue but the delay means the spacecraft is now expected to reach 16 Psyche in 2029.
It will travel around 3.6 billion km on its journey, about 1.4 million km further than its route had it launched in 2022.
The new course will see the Psyche spacecraft make a close pass of Mars, slingshotting around the planet to gather speed on its journey to the full metal asteroid.
What do we already know about 16 Psyche?
The study of 16 Psyche has, so far, been limited to observations from Earth and in low-Earth orbit.
The asteroid is the largest member of the M-class, a group of metal-rich asteroids. These are a rare breed; there are less than 40 in JPL's Small Body Database.
Compared with many other asteroids, 16 Psyche is very, very reflective.
That reflectiveness has enabled scientists to build a fuzzy picture of 16 Psyche's structure and key features, Professor Shepard said.
"We know its size, shape, rotation period, and rotation pole to a pretty high degree — within 5 per cent or so."
It's about 220km wide — you could fit two side-by-side between Melbourne and Launceston — and shaped like a bumpy, flattened potato.
The Psyche spacecraft will hover about 75km from its surface.
That's about eight times closer than a Starlink satellite in low-Earth orbit.
At this height, the spacecraft will be able to image the surface features, creating a map of Psyche and providing our first real glimpse of its surface features — a real-world equivalent of the "zoom and enhance" trope used in TV crime dramas.
What metals are on 16 Psyche?
The surface of 16 Psyche remains a riddle wrapped in an enigma adorned with a coating of rare metals — we think.
Data from large telescopes and radar imaging have shown some patches reflect more light than others, suggesting those metals are distributed haphazardly over Psyche's surface.
What those metals are remains elusive.
We do know that many meteorites — the rocks that fall to Earth from space — come from asteroids. Scientists can study their chemical composition and structure to determine which asteroids they may have originated from.
"We use the metals that have been observed in iron meteorites as examples for what metal Psyche might be made of," said Fiona Nichols-Fleming, a PhD candidate at Brown University in the US studying 16 Psyche.
It's very likely the asteroid is rich in iron and nickel and there's also likely to be trace elements of cobalt, titanium and rare metals, like platinum and palladium.
But while this provides the best guess at what metals might be on the asteroid, the truth is scientists aren't yet sure of their abundance.
What don't we know about 16 Psyche?
The biggest question is: What is 16 Psyche?
There are a number of competing theories.
One of the earliest theories suggest the asteroid might be a remnant core of a planet, left over from the earliest days of the Solar System. Later measurements of the rock's density have suggested this is less likely, Professor Shepard said.
"I don't think any theory has been completely ruled out, but the earliest idea that Psyche is a remnant metal core is probably the least favoured right now."
If it is a remnant core, the Psyche spacecraft will find out. It carries a magnetometer, hoping to sense any remnant magnetism the asteroid might exhibit.
Another theory suggests 16 Psyche may have been moulded by an extreme type of volcanism that is no longer active.
There are so many unanswered questions about Psyche's formation and evolution, Ms Nichols-Fleming said.
"Regardless of what the mission finds, we'll have a new piece of the puzzle for understanding the early Solar System and the formation of planetary bodies."
How much is 16 Psyche worth?
That's the $US10,000 quadrillion ($15,600 quadrillion) question.
Lindy Elkins-Tanton, lead mission scientist, once suggested the asteroid could be worth that amount.
That number is highly speculative, as Professor Elkins-Tanton noted in a 2017 interview, and the bigger problem is we'd have to find a way to mine its minerals.
16 Psyche would be a great resource, said Andrew Tomkins, an earth and planetary scientist at Monash University, "if you can find a way to bring it down to the Earth's surface ... without making a big hole in the ground".
The idea of mining the asteroid remains a pipe dream, though, because scientists don't know enough about Psyche's surface features and composition.
Professor Shepard noted it would be foolhardy to rush to the asteroid with a stack of mining equipment before we have this type of preliminary information to plan our journey.
Rebecca Allen, an astronomer at Swinburne University of Technology, says "there are going to be insane challenges you have to overcome, and advancing technology to do that is going to come back to us and benefit us on the planet".
There are other issues at play, too. Who owns an asteroid? Under the conditions of the 1967 United Nations Outer Space Treaty, the answer is "nobody".
Signatories to the treaty, including the US, Russia, India, China and Australia, can't claim sovereignty over asteroids, the Moon or Mars.
However, the Treaty does not explicitly deny countries access to resources they've mined.
And while turning space rocks into space mines remains hypothetical and exorbitantly expensive, missions like Psyche could pave the way for developing the technological know-how and understanding that could come back to benefit us on Earth, Dr Allen noted.
But sustainability, safety and the ethical considerations of asteroid mining must be considered, too.
"We have to think about the consequences of what we're doing there," Dr Allen said.
How can I watch the launch?
NASA and SpaceX will both be streaming the launch live on October 12, but you'll need to be up late.
The launch time is 1:38am AEDT, but broadcasts generally start 30 to 60 minutes prior to lift-off. | Chemistry and Material Sciences |
Numerous asteroids that have punctured the surface of dwarf planet Ceres also appear to have influenced its reservoir of precious organic molecules.
In 2017, scientists studying data sent home by NASA's Dawn spacecraft initially spotted organic compounds known as aliphatic molecules near a 32-mile-wide impact crater on Ceres. Since then, they have been trying to pin down the origin of these molecules; few studies suggested asteroids delivered them to the dwarf planet while others concluded they were formed on Ceres itself.
"We are finding that organics may be more widespread than first reported and that they seem to be resilient to impacts with Ceres-like conditions," Juan Rizos, an astrophysicist at the Instituto de Astrofisica de Andalucia in Spain and a co-author of the new study, said in a statement.
To arrive at their conclusions, Rizos and his colleagues carried out a series of experiments mimicking the impact conditions expected on Ceres at NASA's Ames Vertical Gun Range in California, a facility dedicated to simulating the physics and mechanics of impact cratering and asteroid strikes. The team also merged data from the camera and imaging spectrometer on Dawn, and the two datasets together allowed the team to map organic-rich areas on Ceres in greater detail than previously done.
The findings collectively show a "good correlation" of organics with areas hosting older impacts, researchers say, showing that asteroid strikes did indeed influence the presence and abundance of organics across billions of years.
"While the origin of the organics remains poorly understood, we now have good evidence that they formed in Ceres and likely in the presence of water. There is a possibility that a large interior reservoir of organics may be found inside Ceres," Rizos said in the same statement. "So, from my perspective, that result increases the astrobiological potential of Ceres."
The 2023-2032 decadal survey for planetary science and astrobiology earmarked Ceres as a high priority target for a sample return mission, which might occur several decades into the future.
In the meantime, another NASA probe called Lucy will soon explore 10 trojan asteroids thought to hold clues to the creation of our solar system and even Earth, thanks to hosting material from the early solar system.
"We will likely find differences, as the Trojan asteroids have experienced very different impact histories from Ceres," said Rizos, "and because there are two compositionally different types of Trojan asteroids." Comparing data from the Lucy mission to that gathered by Dawn will help us better understand how these organic molecules are sprinkled throughout the outer solar system, she added.
This research was presented Tuesday (Oct. 17) at the Geological Society of America's GSA Connects 2023 meeting. | Chemistry and Material Sciences |
Researchers using NASA’s James Webb Space Telescope have detected evidence for quartz nanocrystals in the high-altitude clouds of WASP-17 b, a hot Jupiter exoplanet 1,300 light-years from Earth. The detection, which was uniquely possible with Webb’s MIRI (Mid-Infrared Instrument), marks the first time that silica (SiO2) particles have been spotted in an exoplanet atmosphere.
“We were thrilled!” said David Grant, a researcher at the University of Bristol in the U.K. and first author on a paper being published today in the Astrophysical Journal Letters. “We knew from Hubble observations that there must be aerosols – tiny particles making up clouds or haze – in WASP-17 b’s atmosphere, but we didn’t expect them to be made of quartz.”
Silicates (minerals rich in silicon and oxygen) make up the bulk of Earth and the Moon as well as other rocky objects in our solar system, and are extremely common across the galaxy. But the silicate grains previously detected in the atmospheres of exoplanets and brown dwarfs appear to be made of magnesium-rich silicates like olivine and pyroxene, not quartz alone – which is pure SiO2.
The result from this team, which also includes researchers from NASA’s Ames Research Center and NASA’s Goddard Space Flight Center, puts a new spin on our understanding of how exoplanet clouds form and evolve. “We fully expected to see magnesium silicates,” said co-author Hannah Wakeford, also from the University of Bristol. “But what we’re seeing instead are likely the building blocks of those, the tiny ‘seed’ particles needed to form the larger silicate grains we detect in cooler exoplanets and brown dwarfs.”
Detecting Subtle Variations
With a volume more than seven times that of Jupiter and a mass less than one-half of Jupiter, WASP-17 b is one of the largest and puffiest known exoplanets. This, along with its short orbital period of just 3.7 Earth days, makes the planet ideal for transmission spectroscopy: a technique that involves measuring the filtering and scattering effects of a planet’s atmosphere on starlight.
Webb observed the WASP-17 system for nearly 10 hours, collecting more than 1,275 brightness measurements of 5- to 12-micron mid-infrared light as the planet crossed its star. By subtracting the brightness of individual wavelengths of light that reached the telescope when the planet was in front of the star from those of the star on its own, the team was able to calculate the amount of each wavelength blocked by the planet’s atmosphere.
What emerged was an unexpected “bump” at 8.6 microns, a feature that would not be expected if the clouds were made of magnesium silicates or other possible high-temperature aerosols like aluminum oxide, but which makes perfect sense if they are made of quartz.
Crystals, Clouds, and Winds
While these crystals are probably similar in shape to the pointy hexagonal prisms found in geodes and gem shops on Earth, each one is only about 10 nanometers across – one-millionth of 1 centimeter.
“Hubble data actually played a key role in constraining the size of these particles,” explained co-author Nikole Lewis of Cornell University, who leads the Webb Guaranteed Time Observation (GTO) program designed to help build a three-dimensional view of a hot Jupiter atmosphere. “We know there is silica from Webb’s MIRI data alone, but we needed the visible and near-infrared observations from Hubble for context, to figure out how large the crystals are.”
Unlike mineral particles found in clouds on Earth, the quartz crystals detected in the clouds of WASP-17 b are not swept up from a rocky surface. Instead, they originate in the atmosphere itself. “WASP-17 b is extremely hot – around 2,700 degrees Fahrenheit (1,500 degrees Celsius) – and the pressure where the quartz crystals form high in the atmosphere is only about one-thousandth of what we experience on Earth’s surface,” explained Grant. “In these conditions, solid crystals can form directly from gas, without going through a liquid phase first.”
Understanding what the clouds are made of is crucial for understanding the planet as a whole. Hot Jupiters like WASP-17 b are made primarily of hydrogen and helium, with small amounts of other gases like water vapor (H2O) and carbon dioxide (CO2). “If we only consider the oxygen that is in these gases, and neglect to include all of the oxygen locked up in minerals like quartz (SiO2), we will significantly underestimate the total abundance,” explained Wakeford. “These beautiful silica crystals tell us about the inventory of different materials and how they all come together to shape the environment of this planet.”
Exactly how much quartz there is, and how pervasive the clouds are, is hard to determine. “The clouds are likely present along the day/night transition (the terminator), which is the region that our observations probe,” said Grant. Given that the planet is tidally locked with a very hot day side and cooler night side, it is likely that the clouds circulate around the planet but vaporize when they reach the hotter day side. “The winds could be moving these tiny glassy particles around at thousands of miles per hour.”
WASP-17 b is one of three planets targeted by the JWST Telescope Scientist Team’s Deep Reconnaissance of Exoplanet Atmospheres using Multi-instrument Spectroscopy (DREAMS) investigations, which are designed to gather a comprehensive set of observations of one representative from each key class of exoplanets: a hot Jupiter, a warm Neptune, and a temperate rocky planet. The MIRI observations of hot Jupiter WASP-17 b were made as part of GTO program 1353.
More About the Mission
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and the Canadian Space Agency.
MIRI was developed through a 50-50 partnership between NASA and ESA. NASA’s Jet Propulsion Laboratory in Southern California led the U.S. efforts for MIRI, and a multinational consortium of European astronomical institutes contributes for ESA. George Rieke with the University of Arizona is the MIRI science team lead. Gillian Wright is the MIRI European principal investigator.
The MIRI cryocooler development was led and managed by JPL, in collaboration with Northrop Grumman in Redondo Beach, California, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
To learn more about Webb, go here: | Chemistry and Material Sciences |
NASA's Perseverance rover is scurrying around on the Red Planet, wheeling and dealing around Jezero Crater and inspecting the site of this former lake up close.
The rover recently came across some eye-catching circular rock structures, and they are attention-grabbers for good reason. That's because they resemble ones formed by microbial communities in some lakes on Earth.
But the finding underscores, perhaps, how Mother Nature on the Red Planet can make it difficult to conclude what might or might not constitute evidence for life on that world.
Or, on the other hand, could we be missing something?
Several top Mars specialists offer their thoughts and advice on what's the real gist from Jezero.
Too good to be true
"I was genuinely excited when I first saw these circular features because of what I imagined microbialite structures might look like after a lake dries up and erosion takes over," said Steve Ruff, an Arizona State University planetary geologist with a focus on the mineralogy of Mars at the School of Earth and Space Exploration.
Microbialites are rock-like underwater structures that take on the look of reefs but consist mainly of millions of microbes.
"But it also seemed too good to be true and I quickly recognized details that are inconsistent with a biologic origin," Ruff told Space.com.
Ruff said that, because it's Mars, with no confirmed proof of life, you've got to always first assume that biology is not involved and look for geologic explanations.
"Only when there's no compelling geologic explanation should biology be seriously considered. Even then, there needs to be extraordinary evidence, as Carl Sagan said, to claim evidence for life," Ruff advised.
As an independent Mars sleuth, Ruff added that he is hopeful that Perseverance rover science members can actually address what they concluded about these features.
Alternative explanations
Alexis Rodriguez, a senior scientist of the Planetary Science Institute in Tucson, Arizona said that anything that could point to life from such a distant past deserves serious attention.
"My understanding is that while the circular features are considered to be possible evidence of stromatolite-like mounds, the evidence is not unequivocal and it seems that some alternative explanations have not been ruled out," Rodriguez said. "However, if they are indeed biogenic features there are numerous important implications of interest to the general public."
For example, Rodriguez said that the persistence of stromatolites in a given geological setting suggests a stable, long-term presence of liquid water, as they require time for formation.
"Hence, their existence implies that the water in those locales did not freeze for extended periods, allowing for the continual biological activity necessary for stromatolite growth," Rodriguez added. "This implication carries tremendous weight on our understanding of Mars' early climate, touching on the debate on whether it was mostly much colder than that of early Earth or a much closer match."
Meeting the criteria
It is true that nature is more creative than we could imagine, said Catherine Gillen of Durham University in the U.K., working on the Exploring Uncertainty and Risk in Contemporary Astrobiology (EURiCA) project that seeks to define and establish the definitions of what constitutes astrobiology, the study of the origins of life throughout the universe.
"There does indeed seem to exist a biological explanation for these circular rock structures due to their similarity with microbial structures on Earth," Gillen said.
"However, the researchers were right not to just leave it there! The resemblance to corestones seems to offer a promising abiotic [not living or composed of living things] explanation that should be preferred over any biological one," said Gillen. "As such, these structures would likely not meet the criteria for biosignature under the proposed definition."
Defining a biosignature
Gillen is the lead author of a recently published paper in the journal "Astrobiology" making a call for a "new definition" of biosignature.
Gillen and colleagues note that the term biosignature has been useful to the community, but its meaning remains unsettled.
Indeed, existing definitions conflict greatly over the balance of evidence needed to establish a biosignature, they report, which leads to mix-ups and puzzlement about what is being claimed when biosignatures are purportedly detected.
In an attempt to resolve this, Gillen and associates suggest the term "biosignature" is used to describe any phenomenon for which biological processes are a known possible explanation and whose potential abiotic causes have been reasonably explored and ruled out.
The thrust of their call is to narrow the gap between the detection of a biosignature and a confirmed discovery of life.
Images are not enough
Underscoring the tough slog up a slippery slope to hopefully rise to a level of evidence needed to make a compelling case for life on Mars is Chris McKay of NASA's Ames Research Center.
A noted Mars specialist, McKay is also an associate editor of the "International Journal of Astrobiology." He recalls receiving a paper about a year ago making the same general claim for Perseverance rover imagery of rocks that look like life.
"Perseverance, unlike the Curiosity Mars rover, has a Raman spectrometer. I asked the author to get the corresponding Raman spectrum and see if there was any organic signal consistent with biological organics. The author tried but there was nothing there," said McKay. "My view is that the images are not enough … way too ambiguous to make a case for something as interesting as life."
Meanwhile, as the Perseverance wheels turn, the robot continues to roll out scientific offerings from Jezero Crater. It is possible that microbial life could have lived there and is preserved in that location.
But sorting out that story is indeed a painstaking and meticulous process … so stay tuned! | Chemistry and Material Sciences |
An ocean world first discovered in 2017 has provided new evidence that it may be closer to our world than previously thought. K2-18 b is a very alluring target for astronomers in the search for life beyond our own planet. Previous observations of the planet suggest it’s an ocean world, and now Webb’s observations suggest it could have carbon-based molecules in the atmosphere.
New results captured by James Webb suggest that traces of both carbon dioxide and methane have been discovered in the atmosphere of K2-18 b. The planet was already intriguing enough because it is located within the habitable zone of its star system. The habitable zone of a star system is defined when a planet orbits within a small area of space that allows for the existence of liquid water.
These areas are typically when the planet is not too hot or too cold, allowing for liquid water and other possible factors of life to exist. The fact that the Webb telescope discovered evidence of carbon molecules is exciting. But what is really exciting is that Webb observed everything here without detecting ammonia, which helps bolster the possibility that K2-18 b is, in fact, an ocean world.
“Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” research lead author and University of Cambridge scientist Nikku Madhusudhan explained in a statement. “Traditionally, the search for life on exoplanets has focused primarily on smaller rocky planets, but the larger Hycean worlds are significantly more conducive to atmospheric observations.”
The initial research here also suggests that a molecule known as dimethyl sulfide (DMS) could be present in the atmosphere. Here on Earth, this molecule is only produced by life, which could mean some form of phytoplankton is living in the oceans of K2-18 b. Of course, that’s all based on the evidence that is presented in these new details, and none of it has been proven with scientific certainty.
The possibility that life could exist on this ocean world is exciting, though, and certainly something for Webb enthusiasts to look forward to. | Chemistry and Material Sciences |
Astronomers have discovered a two-faced star and are baffled by its bizarre appearance.
The white dwarf appears to have one side composed almost entirely of hydrogen and the other side made up of helium. It is the first time that astronomers have discovered a lone star that appears to have spontaneously developed two contrasting faces.
“The surface of the white dwarf completely changes from one side to the other,” said Dr Ilaria Caiazzo, an astrophysicist at Caltech who led the work. “When I show the observations to people, they are blown away.”
The object, which is more than 1,000 light years away in the Cygnus constellation, has been nicknamed Janus, after the two-faced Roman god of transition, although its formal scientific name is ZTF J203349.8+322901.1. It was initially discovered by the Zwicky Transient Facility (ZTF), an instrument that scans the skies every night from Caltech’s Palomar Observatory near San Diego.
Caiazzo was searching for white dwarfs and one candidate star stood out due to its rapid changes in brightness. Further observations revealed that Janus was rotating on its axis every 15 minutes. Spectrometry measurements, which give the chemical fingerprints of a star, showed that one side of the object contained almost entirely hydrogen and the other almost entirely helium.
If seen up close, both sides of the star would be bluish in colour and have a similar brightness, but the helium side would have a grainy, patchwork appearance like that of our own sun, while the hydrogen side would appear smooth.
The star’s two-faced nature is difficult to explain as its exterior is made of swirling gas. “It’s hard for anything to be separated,” Caiazzo said.
One explanation is that Janus could be undergoing a rare transition that has been predicted to occur during white dwarf evolution.
White dwarfs are the simmering remains of stars that were once like our sun. As the stars age, they puff up into red giants. Eventually, the fluffy outer material is blown away and the core contracts into a dense, fiery, hot white dwarf with roughly the mass of our sun while being only the size of Earth.
The star’s intense gravitational field causes heavier elements to sink to the core and the lighter elements to float, creating a two-tier atmosphere of helium below, topped with a thin layer of hydrogen (the lightest element). When the star cools below about 30,000C (54,032F), the thicker helium layer begins to bubble, causing the outer hydrogen layer to get mixed in, dilute and disappear from view.
“Not all but some white dwarfs transition from being hydrogen- to helium-dominated on their surface,” Caiazzo said. “We might have possibly caught one such white dwarf in the act.”
If so, the scientists believe that an asymmetric magnetic field could be causing the transition to occur in a lopsided way. “If the magnetic field is stronger on one side, it could be limiting convection [bubbling in the helium layer],” Caiazzo said. “On the other side, convection could be winning out and so the hydrogen layer has been lost.”
The findings are published in the journal Nature. | Chemistry and Material Sciences |
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
The James Webb Space Telescope and other observatories witnessed a massive explosion in space that created rare chemical elements, some of which are necessary for life.
The explosion, which occurred on March 7, was the second brightest gamma-ray burst ever witnessed by telescopes in more than 50 years of observations, over one million times brighter than the entire Milky Way Galaxy combined. Gamma-ray bursts are short emissions of the most energetic form of light.
This particular burst, called GRB 230307A, was likely created when two neutron stars — the incredibly dense remnants of stars after a supernova — merged in a galaxy about one billion light-years away. In addition to releasing the gamma-ray burst, the merger created a kilonova, a rare explosion that occurs when a neutron star merges with another neutron star or a black hole, according to a study published Wednesday in the journal Nature.
“There are only a mere handful of known kilonovas, and this is the first time we have been able to look at the aftermath of a kilonova with the James Webb Space Telescope,” said lead study author Andrew Levan, astrophysics professor at Radboud University in the Netherlands. Levan was also part of the team that made the first detection of a kilonova in 2013.
In addition to Webb, NASA’s Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, and the Transiting Exoplanet Survey Satellite observed the burst and traced it back to the neutron star merger. Webb was also used to detect the chemical signature of tellurium within the aftermath of the explosion.
Tellurium, a rare metalloid, is used to tint glass and ceramics and has a role in the manufacturing process of rewritable CDs and DVDs, according to the Royal Society of Chemistry. Astronomers expect that other elements close to tellurium on the periodic table, including iodine, which is necessary for much of life on Earth, is likely to be present in the material released by the kilonova.
“Just over 150 years since Dmitri Mendeleev wrote down the periodic table of elements, we are now finally in the position to start filling in those last blanks of understanding where everything was made, thanks to Webb,” Levan said.
Tracking stellar explosions
Astronomers have long believed that neutron star mergers are the celestial factories that create rare elements heavier than iron. But it’s been difficult to track down the evidence.
Kilonovae are rare events, which makes them difficult to observe. But astronomers look for short gamma-ray bursts, which only last about two seconds at the longest, as the telltale byproducts of the scarce events.
What was unusual about this burst is that it lasted for 200 seconds, making it a long gamma-ray burst. Such extended bursts are usually associated with supernovas created when massive stars explode.
“This burst is way into the long category. It’s not near the border. But it seems to be coming from a merging neutron star,” said study coauthor Eric Burns, assistant professor of physics and astronomy at Louisiana State University, in a statement.
Fermi initially detected the gamma-ray burst, and astronomers used ground- and space-based observatories to track the changes in brightness during the aftermath of the explosion in gamma-ray, X-ray, visible, infrared and radio waves of light. The quick changes in visible and infrared light suggested it was a kilonova.
“This type of explosion is very rapid, with the material in the explosion also expanding swiftly,” said study coauthor Om Sharan Salafia, a researcher at the National Institute for Astrophysics’ Brera Astronomical Observatory in Italy, in a statement. “As the whole cloud expands, the material cools off quickly and the peak of its light becomes visible in infrared, and becomes redder on timescales of days to weeks.”
The team also used Webb to trace the journey of the neutron stars before they exploded.
Once, they were two massive stars in a binary system that existed in a spiral galaxy. One of the pair exploded as a supernova, leaving behind a neutron star, and then the same thing happened to the other star. These explosive events launched the stars from their galaxy and they remained as a pair, traveling for 120,000 light-years before merging several hundred million years after being ejected from their home.
Finding cosmic elements
Astronomers have been trying to determine how chemical elements are created in the universe for decades.
Discovering more kilonovas in the future with sensitive telescopes like Webb and the Nancy Grace Roman Space Telescope, set to launch in 2027, could provide insights into which heavy elements are created and released by the rare explosions.
The researchers also want to find more mergers that create longer gamma-ray bursts to determine what drives them and whether there is any connection to the elements created in the process.
The violent life cycle of stars has distributed the elements found on the periodic table throughout the universe, including those necessary for life to form on Earth in the first place. The ability to study stellar explosions like kilonovas in recent years is enabling scientists to answer questions about the formation of chemical elements, allowing for a deeper understanding of how the universe has evolved over time.
“Webb provides a phenomenal boost and may find even heavier elements,” said study coauthor Ben Gompertz, assistant professor at the Institute for Gravitational Wave Astronomy and the School of Physics and Astronomy at the University of Birmingham in the United Kingdom, in a statement.
“As we get more frequent observations, the models will improve and the spectrum may evolve more in time,” Gompertz said. “Webb has certainly opened the door to do a lot more, and its abilities will be completely transformative for our understanding of the universe.” | Chemistry and Material Sciences |
Observation of a refractive index line shape in ultrafast XUV transient absorption spectroscopy
Ultrafast extreme ultraviolet (XUV) spectroscopy is a powerful technique for probing the dynamics of atoms and molecules with attosecond time resolution. However, conventional XUV absorption measurements only provide information about the imaginary part of the complex refractive index, which is related to the absorption coefficient. The real part of the refractive index, which describes the chromatic dispersion of the material, is usually inaccessible.
In a new study published in Ultrafast Science, Mingze Sun et al. have demonstrated a novel method to measure the refractive index line shape in ultrafast XUV transient absorption spectroscopy. They used a scheme where the XUV pulse traverses the target gas jet off-center, which induces deflection on the XUV radiation due to the density gradient of the jet. By measuring the frequency-dependent XUV deflection spectra, they were able to reproduce the refractive index line profile.
The researchers also showed that they could control the refractive index line shape by introducing a later-arrived near-infrared pulse to modify the phase of the XUV free induction decay, resulting in different XUV deflection spectra. This technique allowed them to manipulate the matter response to the XUV light field and explore new physical phenomena.
The study reveals new insights into matter-induced absorption and deflection in ultrafast XUV spectroscopy. The real refractive index and the absorption index may be measured simultaneously, which provides a full picture of a material's linear response to incident light.
More information: Mingze Sun et al, Observation of Refractive Index Line Shape in Ultrafast XUV Transient Absorption Spectroscopy, Ultrafast Science (2023). DOI: 10.34133/ultrafastscience.0029
Provided by Ultrafast Science | Chemistry and Material Sciences |
When Evgenii Krestianinov first handled a 5cm-wide meteorite fragment, he never dreamed that inside it contained a secret about the birth of our solar system.
The Russian-born cosmochemist's adventure began while he was studying in Canberra, and his supervisor purchased a piece of the Erg Chech 002 rock and charged him with dating it. The rock itself didn’t initially appear to be anything special — dozens of its fractured pieces are up for sale on eBay for as little as $11.
It was already known that Erg Chech 002 is so ancient it predates the Earth and it is the oldest volcanic rock known to humankind. But by analysing several types of isotopes in the meteorite, Mr Krestianinov was able to generate one of the most precise ages of a space object — 4.56556 billion years.
Speaking with Yahoo News Australia on Tuesday night, just hours before his paper was published in the journal, Nature Communications, Mr Krestianinov recalled the moment he made the discovery. “I was surprised but it wasn’t a eureka moment. It was more like: Hmmm, maybe I need to check my data again. So I checked it again,” he said.
How meteorite discovery will change our understanding of solar system
While discovering an accurate date during his time at Australia National University was “exciting”, the researcher revealed he’s made a much bigger game-changing discovery. After comparing older analysis of other meteorites with his more accurate reading of Erg Chech 002, he found it contained much higher concentrates of an unstable element called aluminium-26.
This means that contrary to popular assumption, aluminium-26 was irregularly distributed across the early solar nebula — a rotating interstellar cloud of dust and gas.
Mr Krestianinov's discovery is important because aluminium-26 is frequently used as a measurement tool to estimate the ages of meteorites from that time.
Now, Mr Krestianinov believes many of the dates given to other ancient objects could be inaccurate, so his discovery could enhance the ability of researchers to build a more accurate picture of the early history of our solar system.
Love Australia's weird and wonderful environment? Get our new weekly newsletter showcasing the week’s best stories. | Chemistry and Material Sciences |
A new study suggests that Earth’s hotter sister (Venus is roughly 100 times hotter than Earth) could have formed by Earth-like plate tectonics billions of years ago. The study is published in Nature Astronomy and discusses how atmospheric data from Venus, alongside computer modeling, has delivered them to this particular resolution.
See, Venus is a lot like Earth. In many ways, it is considered Earth’s evil twin. However, because of its distance from the Sun and the thickness of its atmosphere, Venus is exceptionally brutal, destroying and crushing any spacecraft that travel there within just two hours. However, we continue to find similarities between it and our own planet.
This new study, which discusses the potential of early Earth-like plate tectonics on Venus, could help us grasp a better understanding of how Venus formed. That, along with other data, could one day help us better understand what happened to Venus to make it such a hellscape of a planet.
On Earth, plate tectonics played a vital role in forming the various continents, mountains, and chemical reactions that stabilized our planet’s surface temperature. On Venus, though, things are different. For the most part, scientists believe that Venus has a “stagnant lid,” which is essentially just a single tectonic plate with minimal amounts of give.
If true, that means that most of the gasses inside of Venus have remained trapped beneath the list of the outer crust for billions of years, turning it into the ball of death that it now is. However, data from Venus’ atmosphere, as well as computer modeling, have painted a slightly different picture.
The new data instead shows that for Venus to reach its current state, Venus may have had plate tectonics between 4.5 billion and 3.5 billion years ago, after the planet formed. However, the early tectonic movements would probably have been limited, just like early Earth plate tectonics were limited. Somewhere along the way, though, those multiple plates formed into the stagnant lid responsible for Venus’ current makeup.
But what exactly does this mean? Well, it means that 4.5 billion years ago, Venus may have had the right conditions to support microbial life, and Venus probably had oceans, too. This would have made Venus and Earth even more alike than scientists previously believed. | Chemistry and Material Sciences |
Today marks the final step of NASA’s OSIRIS-REx mission, which launched in September 2016, as a small capsule containing a sample of the asteroid Bennu descends through the Earth’s atmosphere, landing in the Utah desert for NASA to collect and analyze. This is similar to the method used to collect particles from a comet with the Stardust mission that dropped off a sample in Utah in 2006.
The audacious mission flew the spacecraft to a small, near-Earth asteroid named Bennu and attempted something that hadn’t been done before by orbiting the asteroid, getting close enough to scrape up some material and collect it, and then returning to Earth with the sample. NASA TV will stream coverage of the sample return on its YouTube channel starting at 10AM ET today.
After OSIRIS-REx launched, it employed a slingshot maneuver to sweep around the earth and use its gravity to fling it towards Bennu — you know, like the time The Enterprise whipped around the sun to go back in time and save the whales in Star Trek IV: The Voyage Home. OSIRIS-REx collected even more than the 60 grams of Bennu material NASA was aiming for when it made the scoop in 2020 before starting its trip back to Earth in 2021.
Follow along here for all of the updates about the OSIRIS-REx asteroid sample return.
Highlights
- NASA’s asteroid-punching spacecraft begins its trek back home
- Stunning images show NASA’s OSIRIS-REx spacecraft stirring up rocks on an asteroid
- NASA’s OSIRIS-REx spacecraft successfully taps an asteroid in attempt to grab a sample
- NASA is about to launch a spacecraft to an asteroid to learn more about life on Earth
May 10, 2021
The NASA spacecraft that snatched a sample of rocks from the distant Bennu asteroid last year fired up a suite of thrusters on Monday and committed to its two-year journey back home. The maneuver kicks the minivan-sized spacecraft, dubbed Osiris-REx, onto a winding cosmic path around the Sun and toward Earth’s orbit. When it returns to Earth in 2023, it’ll toss a capsule packed with asteroid samples through the atmosphere somewhere over Utah.Read Article >
The spacecraft’s Asteroid Departure Maneuver (ADM) was no sweat for the Osiris-REx team, but it marked a significant step towards the return of the first pristine cache of asteroid samples in NASA’s history. Spacecraft engineers inside a Lockheed Martin center in Littleton, Colorado confirmed the seven-minute thruster firing began at 4PM ET Monday and celebrated success shortly after.
Oct 29, 2020
NASA’s OSIRIS-REx spacecraft has successfully stored a small cache of rocks that it grabbed from the surface of an asteroid named Bennu last week, sealing the pebbles inside the vehicle’s belly. The asteroid particles will now remain inside the spacecraft over the next three years, as OSIRIS-REx makes its way back to Earth.Read Article >
OSIRIS-REx grabbed the sample on October 20th of last week, more than four years after launching from Earth on its mission to touch an asteroid. Using a thin robotic arm, the vehicle lightly tapped the asteroid Bennu, stirring up rocks on the surface and pushing some of the pebbles up into the spacecraft.
Oct 23, 2020
NASA’s OSIRIS-REx spacecraft did its job a little too well on Tuesday, when it tried to scoop up a handful of rocks from an asteroid named Bennu more than 200 million miles from Earth. The vehicle actually grabbed too much material with its robotic arm, jamming the lid at the end of the arm open — and letting part of the asteroid sample escape out into space.Read Article >
“We were almost a victim of our own success here,” said Dante Lauretta, the principal investigator for the OSIRIS-REx mission at the University of Arizona, in a press conference.
Oct 21, 2020
NASA shared astonishing images of its OSIRIS-REx spacecraft touching an asteroid yesterday, revealing how the vehicle stirred up rocks and debris on the object’s surface when it made contact. The goal of the tap was to collect a sample of material from the asteroid, but the engineers behind the spacecraft say they won’t for sure if they collected anything until this weekend, when they spin the vehicle and measure how much material is inside.Read Article >
However, the OSIRIS-REx team feels confident that they got something. “Bottom line is from analysis of the images that we’ve gotten down so far, is that the sampling event went really well, as good as we could have imagined it would,” Dante Lauretta, the principal investigator of OSIRIS-REx at the University of Arizona, said during a press conference. “And I think the chances that there’s material inside... have gone way up way up based on the analysis of the images.”
This afternoon, a NASA spacecraft more than 200 million miles from Earth successfully touched the surface of an asteroid, in an attempt to grab a handful of pebbles and dust from the space rock. Data from the spacecraft confirmed that the vehicle did indeed touch the asteroid today, but NASA won’t know until tomorrow if it actually snagged a sample of material.Read Article >
“Touchdown declared,” a mission controller announced when the team received data confirming the maneuver. “Sampling in process.” The news of the success was met with cheers and applause from engineers following along with the procedure.
This afternoon, NASA’s OSIRIS-REx spacecraft will grab a small sample of rocks from the surface of an asteroid named Bennu zooming through space more than 200 million miles from Earth. It’s an ambitious task, but if it works, OSIRIS-REx may eventually return to Earth with the largest sample of material from another space body since NASA’s Apollo missions to the Moon.Read Article >
The OSIRIS-REx spacecraft has been circling Bennu for the last two years, mapping its surface and hunting for the right spot to snag these rocks. After an intense amount of planning from the mission team, the engineers have a target all picked out on Bennu and are ready to send their spacecraft down to the surface. OSIRIS-REx will lightly touch the surface of Bennu with an extended robotic arm, which will then blast air onto the rocks and stir things up. The blast should send pebbles and dust up into the arm. The rubble will then be stored inside the spacecraft for the long journey home.
Oct 19, 2020
Tomorrow, a US spacecraft more than 200 million miles from Earth will sneak up to an asteroid larger than the Empire State Building and snag a handful of rocks from its surface. If all goes to plan, the spacecraft will store the precious cache of rocks inside its belly, and will eventually transport the materials to Earth, where they can be studied by scientists in a lab.Read Article >
The spacecraft stealing these rocks is called OSIRIS-REx, part of the first-ever NASA mission tasked with returning samples of an asteroid back to Earth. Launched in September of 2016, OSIRIS-REx spent two years traveling to an asteroid named Bennu. Since it arrived in 2018, the spacecraft has been circling the asteroid and mapping it in excruciating detail, in order to find just the right spot to scoop up a sample.
Apr 20, 2020
Last Tuesday, a team of engineers sat huddled around their computer screens, monitoring a spacecraft as it maneuvered around a rocky asteroid more than 140 million miles from Earth. They were conducting an important interplanetary dress rehearsal, running the spacecraft through many of the operations it will do in August when it attempts to snag a tiny sample of rocks from the asteroid’s surface. This dress rehearsal has been in the works for years, and the team had expected to be gathered together for it in a mission center in Colorado.Read Article >
Instead, most of them kept tabs on the event from home. “It was a skeleton crew that was supporting the event in person, compared to what was originally planned,” Mike Moreau, deputy project manager for the mission at NASA’s Goddard Space Flight Center, tells The Verge. “More than three-quarters of the team was doing it from home and monitoring remotely.”
Dec 12, 2019
Next year, NASA plans to scoop up a small batch of dirt from an asteroid named Bennu, located millions of miles from Earth — and now the agency knows which part of the space rock it’s going to steal from. Today, the space agency announced that one of its spacecraft will attempt to grab some particles from a 20-meter-wide crater, called Nightingale, on the asteroid.Read Article >
Engineers picked the Nightingale site from four final candidate spots on Bennu, arguing it could be the best place to find organic material and water on the asteroid that may hail from the earliest days of the Solar System. “This one really came out on top, because of the scientific value,” Dante Lauretta, the principal investigator of the asteroid sampling mission, said during a press conference announcing the selection. However, targeting the crater is not without risk. The area is surrounded by a large wall of rocks, which could make it difficult to grab a sample. But ultimately, Lauretta said the area could have what they’re looking for.
Jun 17, 2019
NASA’s asteroid-sampling spacecraft OSIRIS-REx just snapped its closest picture yet of Bennu, the deep-space rock it’s been hovering around since the end of last year. The high-resolution image highlights the object’s very rocky surface and even showcases a very large boulder on its southern half.Read Article >
OSIRIS-REx took this up-close picture on June 13th, right after the spacecraft inserted itself into orbit around Bennu for the second time. The vehicle first got into Bennu’s orbit on December 31st, 2018, flying about a mile away from the asteroid’s surface. From that path, OSIRIS-REx mapped Bennu’s surface in intricate detail, and also observed some interesting things from this vantage point, including rocks spewing from Bennu’s surface.
Mar 19, 2019
NASA spacecraft discovers its target asteroid is spewing material and is much more rugged than expected
NASA’s OSIRIS-REx spacecraft made an astonishing discovery about the asteroid it has been orbiting since December: the rock is actively spewing material out into space. The asteroid, named Bennu, has ejected materials up to 11 times since the spacecraft has been there. But no one is sure what exactly is causing these bursts.Read Article >
The revelation is just one of many surprises that scientists have learned about Bennu, ever since OSISIR-REx reached the asteroid late last year. Launched in 2016, OSIRIS-REx is tasked with eventually grabbing a sample from Bennu and then returning it back to Earth, to help scientists better study asteroids — remnants of the early Solar System. But before that happens, the OSIRIS-REx mission team is trying to learn as much as it can about the asteroid using the spacecraft’s instruments.
Dec 10, 2018
Long before it struck out on its own, a distant, small asteroid called Bennu had a wet, watery start, according to new evidence just announced by NASA.Read Article >
NASA’s OSIRIS-REx spacecraft, which arrived at Bennu on December 3rd after a two-year journey, is currently positioned about 12 miles above the surface of the asteroid. It recently sent back data indicating that the asteroid’s surface is littered with clay-like minerals that indicate that parts of this space rock had liquid water at some point in its distant past.
Dec 3, 2018
Today, one of NASA’s deep-space probes, OSIRIS-REx, arrived at the space rock it’s been traveling toward for the last two years, an asteroid named Bennu. At noon ET, OSIRIS-REx came within about 12 miles (20 kilometers) of the asteroid, which is closer than ever before. The arrival means that OSIRIS-REx is now starting a new phase of its mission that entails extensively mapping the surface of the asteroid to find the best place to grab a sample of material.Read Article >
“We have arrived!” Javi Cerna, the OSIRIS-REx telecom engineer at Lockheed Martin, jubilantly proclaimed on NASA TV when the mission team received word that the spacecraft had made it to the asteroid. The announcement was followed by cheers and applause by the team members at the Denver headquarters of Lockheed Martin, the company that built the spacecraft.
Aug 25, 2018
NASA’s asteroid-sampling spacecraft, OSIRIS-REx, has captured its very first images of the deep-space target it’s currently hurtling toward — a nearly half-mile-wide space rock orbiting the Sun named Bennu. It’s a big step for the vehicle as it prepares for its arrival at the asteroid in December of this year.Read Article >
Since the picture was taken from so far away — at a distance of 1.4 million miles — Bennu appears as just a few pixels of light moving across space. But for the OSIRIS-REx team, it shows that their spacecraft is on the right track and that Bennu is right where they expected. “Many of us have been working for years and years and years to get this first image down,” Dante Lauretta, the principal investigator for OSIRIS-REx at the University of Arizona, Tucson, said during a press conference on Friday.
Sep 19, 2017
On Friday, a spacecraft the size of an SUV will slingshot around Earth’s South Pole, altering its trajectory through space. The probe is NASA’s OSIRIS-REx, and its upcoming maneuver around our planet is known as a gravity assist — a way to harness Earth’s gravity to alter its orbit. The move is critical, since it will put OSIRIS-REx on course to meet up with an asteroid in the fall of 2018.Read Article >
OSIRIS-REx launched last year with a relatively straightforward purpose: grab a sample of rocks from an asteroid and bring them back to Earth. If all goes well, the vehicle should retrieve the largest sample ever collected from an asteroid, and give scientists the chance to study the space rock components in more detail than ever before. But first, the probe has to reach its target — a nearby asteroid named Bennu.
Sep 9, 2016
An Atlas V rocket just successfully launched NASA’s OSIRIS-REx vehicle into space from Cape Canaveral, Florida, initiating the spacecraft’s journey to grab a sample from an asteroid and bring it back to Earth. The probe’s expedition isn’t exactly a short one, though. It will take OSIRIS-REx seven years to rendezvous with the asteroid, scoop up a small sample of materials off the space rock, and then return back to our planet. If all goes according to plan, it'll be the first time NASA brings back pieces of an asteroid, allowing researchers to closely study the chemical makeup of Bennu in laboratories here on Earth.Read Article >
OSIRIS-REx is now on its way into a heliocentric orbit. In two weeks, NASA will turn all the spacecraft's instruments on to see if they're working properly. Then it's smooth sailing for OSIRIS-REx, as it spends the next year traveling around the Sun. The spacecraft will eventually swing back by Earth in September 2017 and use the planet’s gravity to change the plane of its orbit, putting it in the same plane as Bennu. Then it’s another year of traveling through space until OSIRIS-REx reaches the asteroid in August 2018.
Sep 8, 2016
On Thursday, a NASA spacecraft will launch on a seven-year round-trip journey to an asteroid with one simple mission: scoop up pieces of the space rock and bring them back to Earth. It’s the space agency’s OSIRIS-REx mission, and if it’s successful, the spacecraft will collect the largest sample ever from a near-Earth asteroid. And those asteroid pieces could tell us a great deal about how the Solar System came to be and possibly how life got started on our planet.Read Article >
Asteroids are thought to be tiny snapshots of the early Solar System. Researchers believe these objects have remained relatively untouched for billions of years, so tapping into one could tell us what the original chemical makeup of the Solar System looked like. There’s also speculation that asteroids may contain the so-called building blocks for life — water, organic molecules, and amino acids. Analyzing an asteroid could then tell us if these space rocks are responsible for bringing life’s precursors to Earth. | Chemistry and Material Sciences |
The moon is 40 million years older than scientists previously thought, according to a new study.
Researchers analysed crystals brought back by Apollo astronauts between 1969 and 1972 to pinpoint the time of the moon's formation.
During Apollo missions, astronauts gathered rocks, pebbles, sand and dust from the moon's surface - and it was lunar dust samples from Apollo 17's final crewed mission used in the study.
They contain zircon crystals that formed billions of years ago, which researchers say are a key indicator of when the moon must have formed.
Scientists believe the moon could have been created from the debris resulting from the Earth being struck a glancing blow by a planetary body about the size of Mars - and the energy from the impact melted the rock which eventually became the moon's surface.
The crystals, which are the "oldest known solids" that formed after the giant impact, according to University of Chicago professor Philipp Heck, suggest the moon is at least 4.46 billion years old.
Theorising on the moon's creation, the professor said: "When the surface was molten like that, zircon crystals couldn't form and survive, so any crystals on the moon's surface must have formed after this lunar magma ocean cooled; otherwise, they would have been melted and their chemical signatures would be erased."
Since the crystals must have formed after the magma ocean cooled, determining their age would reveal the moon's minimum possible age.
Read more:
Astronomers spot most distant cosmic phenomenon
Likely cause of Mars' biggest ever quake revealed
Previous research had suggested the earlier age of the moon, but this study marks the first use of atom probe tomography - analysis of a structure at atomic levels - of the lunar crystal.
The crystal sample was sharpened into a tip using a focused ion beam microscope, then UV lasers were used to evaporate atoms from the tip, lead author of the study Dr Jennika Greer said.
Dr Greer added: "The atoms travel through a mass spectrometer, and how fast they move tells us how heavy they are, which in turn tells us what they're made of."
Many of the atoms found inside the crystals had undergone radioactive decay - a process by which they would have shed some protons and neutrons.
Scientists have established how long it takes this process to occur, and, by looking at the proportion of different uranium and lead atoms (called isotopes) present in a sample, they can tell how old it is - leading to the new conclusion about the moon's age.
Mr Heck, who is also curator in charge of the meteorite and physical geology collections at Chicago's Natural History Field Museum, added: "It's amazing being able to have proof that the rock you're holding is the oldest bit of the moon we've found so far.
"It's an anchor point for so many questions about the Earth. When you know how old something is, you can better understand what has happened to it in its history."
The findings have been published in the journal Geochemical Perspectives Letters. | Chemistry and Material Sciences |
Subscribe to Here’s the Deal, our politics
newsletter for analysis you won’t find anywhere else.
Thank you. Please check your inbox to confirm.
Jeffrey Gillis-Davis, The Conversation
Jeffrey Gillis-Davis, The Conversation
Leave your feedback
In an exciting milestone for lunar scientists around the globe, India’s Chandrayaan-3 lander touched down 375 miles (600 km) from the south pole of the moon on Aug. 23, 2023.
In just under 14 Earth days, Chandrayaan-3 provided scientists with valuable new data and further inspiration to explore the moon. And the Indian Space Research Organization has shared these initial results with the world.
While the data from Chandrayaan-3’s rover, named Pragyan, or “wisdom” in Sanskrit, showed the lunar soil contains expected elements such as iron, titanium, aluminum and calcium, it also showed an unexpected surprise – sulfur.
Planetary scientists like me have known that sulfur exists in lunar rocks and soils, but only at a very low concentration. These new measurements imply there may be a higher sulfur concentration than anticipated.
Pragyan has two instruments that analyze the elemental composition of the soil – an alpha particle X-ray spectrometer and a laser-induced breakdown spectrometer, or LIBS for short. Both of these instruments measured sulfur in the soil near the landing site.
Sulfur in soils near the moon’s poles might help astronauts live off the land one day, making these measurements an example of science that enables exploration.
There are two main rock types on the moon’s surface – dark volcanic rock and the brighter highland rock. The brightness difference between these two materials forms the familiar “man in the moon” face or “rabbit picking rice” image to the naked eye.
The dark regions of the moon have dark volcanic soil, while the brighter regions have highland soil. Image by Avrand6/Wikimedia Commons/CC BY-SA
Scientists measuring lunar rock and soil compositions in labs on Earth have found that materials from the dark volcanic plains tend to have more sulfur than the brighter highlands material.
Sulfur mainly comes from volcanic activity. Rocks deep in the moon contain sulfur, and when these rocks melt, the sulfur becomes part of the magma. When the melted rock nears the surface, most of the sulfur in the magma becomes a gas that is released along with water vapor and carbon dioxide.
Some of the sulfur does stay in the magma and is retained within the rock after it cools. This process explains why sulfur is primarily associated with the moon’s dark volcanic rocks.
Chandrayaan-3’s measurements of sulfur in soils are the first to occur on the moon. The exact amount of sulfur cannot be determined until the data calibration is completed.
The uncalibrated data collected by the LIBS instrument on Pragyan suggests that the moon’s highland soils near the poles might have a higher sulfur concentration than highland soils from the equator and possibly even higher than the dark volcanic soils.
These initial results give planetary scientists like me who study the moon new insights into how it works as a geologic system. But we’ll still have to wait and see if the fully calibrated data from the Chandrayaan-3 team confirms an elevated sulfur concentration.
The measurement of sulfur is interesting to scientists for at least two reasons. First, these findings indicate that the highland soils at the lunar poles could have fundamentally different compositions, compared with highland soils at the lunar equatorial regions. This compositional difference likely comes from the different environmental conditions between the two regions – the poles get less direct sunlight.
Second, these results suggest that there’s somehow more sulfur in the polar regions. Sulfur concentrated here could have formed from the exceedingly thin lunar atmosphere.
The polar regions of the moon receive less direct sunlight and, as a result, experience extremely low temperatures compared with the rest of the moon. If the surface temperature falls, below -73 degrees C (-99 degrees F), then sulfur from the lunar atmosphere could collect on the surface in solid form – like frost on a window.
Sulfur at the poles could also have originated from ancient volcanic eruptions occurring on the lunar surface, or from meteorites containing sulfur that struck the surface and vaporized on impact.
For long-lasting space missions, many agencies have thought about building some sort of base on the moon. Astronauts and robots could travel from the south pole base to collect, process, store and use naturally occurring materials like sulfur on the moon – a concept called in-situ resource utilization.
In-situ resource utilization means fewer trips back to Earth to get supplies and more time and energy spent exploring. Using sulfur as a resource, astronauts could build solar cells and batteries that use sulfur, mix up sulfur-based fertilizer and make sulfur-based concrete for construction.
Sulfur-based concrete actually has several benefits compared with the concrete normally used in building projects on Earth.
For one, sulfur-based concrete hardens and becomes strong within hours rather than weeks, and it’s more resistant to wear. It also doesn’t require water in the mixture, so astronauts could save their valuable water for drinking, crafting breathable oxygen and making rocket fuel.
The Chandrayaan-3 lander, pictured as a bright white spot in the center of the box. The box is 1,108 feet (338 meters) wide. Image shared by NASA/GSFC/Arizona State University
While seven missions are currently operating on or around the moon, the lunar south pole region hasn’t been studied from the surface before, so Pragyan’s new measurements will help planetary scientists understand the geologic history of the moon. It’ll also allow lunar scientists like me to ask new questions about how the moon formed and evolved.
For now, the scientists at Indian Space Research Organization are busy processing and calibrating the data. On the lunar surface, Chandrayaan-3 is hibernating through the two-week-long lunar night, where temperatures will drop to -184 degrees F (-120 degrees C). The night will last until September 22.
There’s no guarantee that the lander component of Chandrayaan-3, called Vikram, or Pragyan will survive the extremely low temperatures, but should Pragyan awaken, scientists can expect more valuable measurements.
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Jeffrey Gillis-Davis is a research professor of physics, arts and sciences at Washington University in St. Louis.
Support Provided By:
Learn more | Chemistry and Material Sciences |
A US$1.2-billion NASA spacecraft launched from Florida today on a 3.6-billion-kilometre journey to a metal-rich asteroid that is unlike anything scientists have studied before.
Its destination is a space rock called Psyche — the largest metallic object in the Solar System. Scientists think this asteroid could be the core of a planet that never finished forming. If so, then studying Psyche will be like getting a time traveller’s look at how the Solar System’s planets formed billions of years ago.
Researchers aren’t completely sure how much of Psyche is metallic, but according to their measurements, “at least part of the surface has got to be actually metal”, says Lindy Elkins-Tanton, a planetary scientist at Arizona State University in Tempe, and the mission’s principal investigator. “That’s the key thing — we want to see that metal surface.”
It will take a while to get to the asteroid, though. The spacecraft, which is also named Psyche, isn’t due to arrive until 2029.
In the meantime, researchers and space enthusiasts are celebrating the ‘heavy metal’ launch: Elkins-Tanton’s team has joked about naming any geological features it finds on Psyche’s surface after heavy-metal bands. And the former lead singer of the metal group Pantera released an ode to the mission, singing that Psyche is “an asteroid of mighty power — this is NASA’s finest hour”.
Space metal
Of the million-plus asteroids in the Solar System, most are composed of rock, or some mixture of rock and ice. Only a few of them — a poorly understood collection known as M-type asteroids — seem to be made mainly of metals, such as iron and nickel. At around 220 kilometres across, Psyche is the largest of the M-type asteroids.
That makes it a strong candidate to be the exposed core of an ancient protoplanet. Researchers think that more than 4.5 billion years ago, soon after the Sun was born, material swirling around our star coalesced into the building blocks of planets. Heat inside these protoplanets partly melted them, allowing their components to separate and form metallic cores, surrounded by rock. Collisions with other space rocks might then have stripped away their rocky exteriors, leaving bare, metal-rich hearts whizzing through space. One of these could be Psyche.
Earth has a similar iron-rich core, but it is buried under thousands of kilometres of rock. So studying Psyche could be a window into understanding planetary interiors, which scientists can’t access directly.
The potato-shaped Psyche orbits the Sun in the main asteroid belt that lies between the orbits of Mars and Jupiter. The spacecraft will fly past Mars in 2026, using the planet’s gravity to speed up a rendezvous with Psyche, arriving there in 2029. It will then spend more than two years orbiting the asteroid, moving progressively closer to the surface as it gathers data on Psyche’s magnetic field, gravity and mineralogical make-up.
For the love of metal
Planetary scientists used to think that Psyche could be composed of as much as 90% metal. But observations with ground- and space-based telescopes gradually showed that it must also contain substantial amounts of rock or other material. The latest estimates suggest that Psyche consists of between 30% and 60% metal1, and that its density is somewhere between that of a pure-iron meteorite and that of a pure-rock meteorite.
“We don’t quite know what it is that’s there along with the metal,” Elkins-Tanton says. If Psyche turns out not to be the metallic core of a protoplanet, another possibility is that it is made of primordial material from the Solar System’s formation that never melted and separated out into layers2.
Recent observations with the James Webb Space Telescope, reported at a planetary-science conference in San Antonio, Texas, on 2 October, hint that Psyche could even contain water, which might be bound up in minerals mixed with metallic grains.
All possibilities are on the table for what Psyche could be — that’s what makes the mission so intriguing, says Katherine de Kleer, a planetary scientist at the California Institute of Technology in Pasadena, who has studied the asteroid3. “There’s a very good chance that we’re going to be surprised,” she says.
The mission ran into several stumbling blocks as it was being developed, including delays related to the COVID-19 pandemic, and a staffing shortage at NASA’s Jet Propulsion Laboratory in Pasadena, California, which has a key role in building the spacecraft. Those problems pushed back the mission’s expected arrival at Psyche from 2026 to 2029. Then, in the final run-up to the launch from the Kennedy Space Center in Florida, engineers discovered problems with the nitrogen thrusters, which are used to control the spacecraft’s orientation as it flies through space and orbits Psyche. To work around the problem, the probe will have to fire the thrusters at a lower power level than was originally planned, for longer periods, to avoid damaging them. | Chemistry and Material Sciences |
NASA's adventurous OSIRIS-REx space capsule that delivered a sample of an asteroid about 200 million miles away is already yielding surprises.
The agency's staff cracked open the space capsule on Tuesday to discover that the inside of the lid is lined with mysterious black material, forcing them to halt work.
Unlike the handful of rocks and dust snatched from the asteroid's surface, the black material looks finer, almost like grime layering a dirty car.
NASA said that the material will undergo a 'quick-look analysis' to see what exactly it is, but a scientist has weighed in ahead of the official verdict.
Speaking to MailOnline, Dr Brad Tucker, an astrophysicist at Australian National University in Canberra, said the fine dust is also likely material from the asteroid.
Timelapse of the 5-minute period on October 20, 2020 when the spacecraft grabbed the sample from Bennu - an asteroid 200 million miles away
'The asteroid dirt is very dark, and fine,' Dr Tucker told MailOnline.
'When OSIRIS-REx did the original touch-and-go maneuver to capture the samples, it had so much the lid could not close.'
NASA admitted shortly after the grab that asteroid material was leaking from OSIRIS-REx, because a stone was jammed in the mechanism.
'Eventually they sorted it out, so this seems likely to be dust and soil from that,' Dr Tucker added.
Since the sample's triumphant return to Earth on Sunday, NASA has only opened the top lid of the capsule, while the rocky handful from Bennu is stashed away in another smaller component within that has to be opened.
The precious cargo is an estimated 8.8 ounces, or 250 grams of rocky material – only about half what you'd find in a average-sized box of cereal.
But NASA thinks it will be enough to reveal secrets about asteroid composition and 'help us better understand the types of asteroids that could threaten Earth'.
The pebbles and dust from Bennu – which could hit the Earth in 2182 – represent the biggest haul from beyond the moon.
It was back in September 2016 that the OSIRIS-REx spacecraft launched from Cape Canaveral, Florida – and it didn't arrive at Bennu until December 2018.
After mapping the asteroid for almost two years, it collected a sample from the surface on October 20, 2020 before returning home – a round trip of 3.86 billion miles.
The craft containing the precious sample touched down on a remote expanse of military land in the western state of Utah on Sunday.
Within two hours of touchdown, the capsule was inside a temporary clean room at the Defense Department's Utah Test and Training Range, having been hoisted there by helicopter.
It was then flown to NASA's Johnson Space Center in Houston, Texas, where experts clad in protective suits opened the initial lid of the capsule on Tuesday and found the black dust.
NASA said in a statement: 'Scientists found black dust and debris on the avionics deck of the OSIRIS-REx science canister when the initial lid was removed.
'These operations are happening in a new laboratory designed specifically for the OSIRIS-REx mission.
'The aluminum lid was removed inside a glovebox designed to enable working with the large piece of hardware.'
In the next few weeks, scientists will completely disassemble the capsule, extract and weigh the sample, create an inventory of the rocks and dust, and then distribute pieces of Bennu to scientists worldwide.
A quarter of the sample will be given to a group of more than 200 people from 38 globally distributed institutions, including a team of scientists from the University of Manchester and the Natural History Museum in London.
Analysis should help researchers better understand the formation of the solar system and how Earth became habitable.
This is because the space rocks are potentially a snapshot of what these planets were like at the time of their formation.
Professor Nick Timms at Curtin University thinks the will Bennu sample could contain 'molecular precursors' to the origin of life.
We – the broader science team – will be making very precise measurements of the structure, texture, minerals, and geochemistry of the sample, right down to nanoscopic scales,' he told MailOnline.
'Chemical and isotopic signatures of the grains and particles that make up the rock fragments can tell us a lot about the processes of how they formed and, in some instances, when they formed and their subsequent history.'
Bennu orbits the sun every 437 days and every six years makes a close approach to Earth – making it a 'potentially hazardous object'
Bennu has a very small chance of hitting Earth in the next century, which would 'be like unleashing 24 atomic bombs', according to an expert.
Studying a sample of it can scientists learn more about its composition and in turn identify ways to be prepared to defend against an impact.
NASA plans to announce its first results from the Bennu sample analysis at a news conference on October 11, which will be livestreamed on the agency's website.
It has been billed as NASA's 'asteroid autumn' and involves a trio of exciting missions that could answer some truly mind-boggling questions. From offering clues to how life on Earth began, to unlocking the secrets of the solar system, key milestones for each voyage are due to play out over the next six weeks. NASA's 'asteroid autumn': MailOnline delves into a trio of exciting missions that have key milestones over the next six weeks. They include the launch of a spacecraft that is going to a '$10,000 quadrillion pace rock', to retrieving a sample from a 4.5 billion-year-old rock that could reveal how life on Earth began. There will also be a fly-by of an asteroid out near Jupiter They include one rocket launch, a distant fly-by between Jupiter and Mars, and the recovery of ancient space rocks in the Utah desert that could contain the ingredients for life. Of the three, the lift-off of NASA's Psyche spacecraft probably sounds the most mundane — but no so fast. That is also a fascinating mission, because it is setting off on a 2.5 billion-mile (4 billion-kilometre) journey to find out once and for all if a metal-rich asteroid really could bring down the world's economy. | Chemistry and Material Sciences |
The extremely early universe featured the most cataclysmic, transformative and energetic events that ever occurred. Driving these energies was the expansion of the cosmos and the resulting fragmentation of the fundamental forces of nature.
And in that fragmentation, massive bubbles may have emerged and collided with each other, powering up energies that would put to shame even our most advanced human-made particle accelerators, new research published June 27 on the preprint database arXiv suggests.
Those awesome energies could have flooded the universe with dark matter particles, microscopic black holes, and much more, the researchers wrote. And the name of those ultra-energetic, early universe structures? Meet the "bubbletrons."
Bubbles of chaos
The four fundamental forces of nature — electromagnetism, strong nuclear, weak nuclear and gravity — are not always so different. At high energies, these forces begin to merge. We can already detect this in our most powerful particle colliders, where electromagnetism and the weak nuclear force merge into a united "electroweak" force. While not proven, physicists strongly suspect that at even higher energies the other forces also merge into a single, unified force.
But the only time the universe had the energies needed to do this was less than a second after the Big Bang. As the cosmos cooled and expanded from that early state, the forces split off from each other in titanic moments of phase transition. This splitting might have been smooth and serene, like the transition of ice melting into water, or incredibly violent, like the transition of water boiling into vapor.
If the transitions were violent, then the universe could have been briefly filled with gigantic bubbles, the new research suggests. Outside these bubbles, the unified forces remained. But inside the bubbles, the cosmos would have been completely different, with the forces split off from each other. Eventually these bubbles would have expanded and collided, completely converting the universe into the new reality.
But these bubbles wouldn't just have come and gone without leaving a trace, fizzing like an opened soda can. The bubbles would have carried truly enormous amounts of energy — orders of magnitude more energy than any human-made or natural process in the present-day cosmos.
The expanding edges of the bubbles could accelerate any nearby particles to incredibly high speeds. Those particles would then slam into others, just like they do in laboratory particle accelerator experiments, creating a shower of released energy and new particles. Additionally, the bubbles would have eventually merged, becoming another source of particle creation.
The researchers discovered that these bubbletrons could have reached the energies necessary to trigger the formation of hypothetical dark matter particles. These particles would have enough mass and abundance to explain the observed amount of dark matter in the universe, according to the team's calculations. They could also have been factories of much more exotic objects, like microscopic black holes that immediately evaporated, adding their energy to the mix.
Most importantly, the researchers discovered that the expansion and collision of the bubbletrons would have created a cacophony of gravitational waves. Those gravitational waves would ring the whole universe like a gigantic bell and persist in the cosmos today, billions of years later.
Recent research points to a universe awash in a background hum of gravitational waves. While most of the waves are likely due to colliding supermassive black holes, some of them might be relics from processes in the extremely early universe, like the rise and fall of bubbletrons. The researchers pointed out that future analysis with pulsar timing arrays, as well as upcoming gravitational waves detectors like LISA and the Einstein Telescope, might be able to find direct evidence for the significant — but fleeting — existence of the bubbletrons.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Paul M. Sutter is a research professor in astrophysics at SUNY Stony Brook University and the Flatiron Institute in New York City. He regularly appears on TV and podcasts, including "Ask a Spaceman." He is the author of two books, "Your Place in the Universe" and "How to Die in Space," and is a regular contributor to Space.com, Live Science, and more. Paul received his PhD in Physics from the University of Illinois at Urbana-Champaign in 2011, and spent three years at the Paris Institute of Astrophysics, followed by a research fellowship in Trieste, Italy. | Chemistry and Material Sciences |
XRISM satellite launches to study the universe in different colors of X-rays
On Sept. 6, a new satellite left Earth; its mission is to tell us about the motions of hot plasma flows in the universe.
Launched from Tanegashima Space Center in Japan, the X-Ray Imaging and Spectroscopy Mission (XRISM) satellite will detect X-ray wavelengths with unprecedented precision to peer into the hearts of galaxy clusters, reveal the workings of black holes and supernovae, as well as to tell us about the elemental makeup of the universe.
XRISM, pronounced "crism," is a collaborative mission between the Japan Aerospace Exploration Agency (JAXA) and NASA, with participation by the European Space Agency.
Unlike existing X-ray telescopes, XRISM will be able to distinguish different colors of X-ray light, unlocking an extraordinary amount of information for scientists. It carries a new type of instrument that detects X-rays through tiny temperature shifts. It will be able to identify what chemical elements are present in the object it's looking at—like iron, nickel, oxygen, or silicon—as well as their abundances. XRISM will also be able to read the velocities of gas motions.
"With XRISM, we will have a whole new view of the hot and energetic universe," said University of Chicago astrophysicist Irina Zhuravleva, who is a NASA participating scientist for the project and a chair of the diffuse extragalactic science team within the collaboration. "We will observe stellar explosions, interactions of black holes with their host galaxies, and violent mergers of galaxy clusters in unprecedented details, but most exciting—the unexpected discoveries that always accompany new missions."
Extreme questions
X-rays are produced by some of the most energetic, extreme phenomena in space: exploding stars, the matter circling around supermassive black holes, and mergers of galaxy clusters—the largest objects in the universe containing thousands of galaxies tied by gravity.
Scientists at UChicago will be analyzing the first observations of several massive galaxy clusters and galaxy groups. A big question relates to supermassive black holes, which sit in the centers of galaxy clusters. Scientists know these black holes release energy into the environment around them, which regulates the rate of star formation. But how exactly these black holes interact with their host galaxies remains an open question.
"So far, we studied the physics of these interactions by looking at 'static' imaging data," explained Zhuravleva, who is the Clare Boothe Luce Assistant Professor of Astronomy and Astrophysics. "With XRISM, we will measure velocities of gas motions driven by supermassive black holes and study the mixing of different gases and metals."
Making similar measurements of the outer regions of galaxy clusters will also reveal how energy is transferred within the universe.
In addition, XRISM will precisely measure the abundances of different chemical elements and the distribution of metals within and outside galaxies—revealing what type of exploding stars are responsible for the current chemical makeup of the universe.
A new era
Because the Earth's atmosphere blocks X-rays, these observations have to be made from space. Launching a satellite and controlling all the instruments from space in an extraordinary challenge. Three attempts have been made previously to launch and operate similar satellites but failed; scientists are hoping the fourth time is the charm for the mission's success.
After its launch, the XRISM satellite will be tested and calibrated to ensure all instruments are ready to begin the observing program later this year.
"XRISM will open a new era of high-resolution X-ray spectroscopy," said Zhuravleva. "We're very excited about this mission and getting ready to analyze highly anticipated data."
Provided by University of Chicago | Chemistry and Material Sciences |
Supermassive black holes affect the chemical composition of their host galaxies, research shows
New research shows that the supermassive black hole at the center of a galaxy can have a direct impact on the chemical distribution of the host galaxy. This provides another piece of the puzzle for understanding how galaxies evolve.
It is well known that active supermassive black holes can produce major changes their host galaxies by heating up and removing the interstellar gas in the galaxy. But the compact sizes of black holes, the long distances from Earth, and obscuration by dust in the galaxies have made it difficult to measure the chemical composition distribution of the gas around an active supermassive black hole.
In this study, an international team of researchers led by Toshiki Saito at the National Astronomical Observatory of Japan and Taku Nakajima at Nagoya University used ALMA (Atacama Large Millimeter/submillimeter Array) to observe the central region of Messier 77 located 51.4 million light-years away in the direction of the constellation Cetus. Messier 77 is a relatively nearby example of a galaxy hosting an active supermassive black hole. Their work has been published in The Astrophysical Journal.
Thanks to ALMA's high spatial resolution and a new machine learning analysis technique, the team was able to map the distribution of 23 molecules. This is the first survey to objectively depict the distribution of all detected molecules through unbiased observations.
The results show that along the path of the bipolar jets emanating near the black hole, molecules commonly found in galaxies such as carbon monoxide (CO) seem to break down, while the concentrations of distinctive molecules such as an isomer of HCN and the cyanide radical (CN) increase.
This is direct evidence that supermassive black holes affect not only the large-scale structure, but also the chemical composition of their host galaxies.
More information: Taku Nakajima et al, Molecular Abundance of the Circumnuclear Region Surrounding an Active Galactic Nucleus in NGC 1068 Based on an Imaging Line Survey in the 3 mm Band with ALMA, The Astrophysical Journal (2023). DOI: 10.3847/1538-4357/ace4c7
Toshiki Saito et al, AGN-driven Cold Gas Outflow of NGC 1068 Characterized by Dissociation-sensitive Molecules, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac80ff
Journal information: Astrophysical Journal
Provided by National Astronomical Observatory of Japan | Chemistry and Material Sciences |
Floating in the middle of our galaxy, near the center of the Milky Way, inside a cloud of gas that swirls at the temperature of 100 Kelvin or -279.67 Fahrenheit, a molecule essential to life on Earth has just been discovered. It sounds inconceivable that such a level of cosmic cold could harbor anything remotely related to a living organism—and yet it does. In fact, without this molecule, humans—and all other breathing, growing things on the planet—would not be possible.
The molecule, which scientists have been trying to detect in space for decades, is carbonic acid, a precursor to amino acids, the basic building blocks of proteins. Its chemical formula is H2CO3. Hardly a household name, carbonic acid nonetheless is key to our capacity to breathe: It ferrets carbon dioxide from our blood into our lungs, where it can be exhaled into the atmosphere. It also plays important roles in various geological processes on Earth. An excess of the molecule in the oceans can lead to ocean acidification. “So while it’s important to life itself, it’s even more important in several atmospheric and geological processes,” says Miguel Sanz-Novo at the Spanish Astrobiology Centre in Madrid. Sanz-Novo’s team confirmed the presence of carbonic acid in space for the first time, publishing their findings in a pre-peer review site called Arxiv.
The findings bolster Panspermia, the theory that life on Earth takes its origin from space and that our planet was “seeded” by various cosmic molecules that took a ride on meteors and meteorites, which later gave rise to organisms.
“The discovery of carbonic acid in space certainly tells us that the chemical ingredients for life are present out there, in the gas that will form new stars and planetary systems,” says Víctor Rivilla, the primary investigator on the project. “So yes, they could have been incorporated into solar system objects such as comets and asteroids, which could have transported them to the early Earth, thus helping to cook the life recipe.”
Our planet may have been “seeded” by various cosmic molecules.
Carbonic acid belongs to a larger group of carboxylic acids. Its close cousins formic acid and acetic acid were first spotted in space in 1971 and 1997, respectively. Scientists suspect that H2CO3 exists in various astronomical environments such as the Galilean icy moons, Mercury’s north polar regions, or even on the surface or atmosphere of Mars—but its presence in space was harder to pinpoint. “This molecule was thought to exist in space somewhere, and now our investigation showed that it is in fact there,” says Sanz-Novo—in the gas from which new stars and planets will eventually form. Moreover, it seems to be quite abundant, Sanz-Novo adds.
Floating inside a cloud named G+0.693-0.027 about 100,000 light-years away from Earth, carbonic acid molecules weren’t easy to discern (researchers used spectroscopy to identify them). Inside that cloud, the molecule exists in a high-energy state, which allows it to do things that it could never do on Earth: For example, as it spins in this high-energy state, it emits photons—massless particles that comprise waves of electromagnetic radiation—with a set frequency. That frequency becomes its spectral fingerprint or a mugshot, explains Sanz-Novo. Detected by two telescopes, at IRAM and Yebes observatories in Spain, and printed on paper, the fingerprint looks almost like a QR code.
Even here on Earth, H2CO3 is not easy to study because in ambient settings of temperature and pressure it easily breaks apart into carbon dioxide and water. To obtain a spectral fingerprint of the molecule in the lab to compare to the telescope’s data, the team also had to get the molecule to a high-energy state so it would start spitting out photons.
The findings aren’t only interesting from the perspective of where life came from, Rivilla adds. They also hint that we may have cosmic neighbors—the comets and asteroids most certainly took the molecules to other planets where they could develop into other life forms. “We all want to know how life could have appeared on our planet—and also if it is or is not a unique event,” he says.
The findings add another piece to the puzzle of whether we are alone in the universe—or not.
Lead image: MarcelClemens / Shutterstock | Chemistry and Material Sciences |
With its sensitive infrared cameras and high-resolution spectrometer, the James Webb Space Telescope (JWST) is revealing new secrets of Jupiter's Galilean satellites, in particular Ganymede, the largest moon, and Io, the most volcanically active.
In two separate publications, astronomers who are part of JWST's Early Release Science program report the first detection of hydrogen peroxide on Ganymede and sulfurous fumes on Io, both the result of Jupiter's domineering influence.
"This shows that we can do incredible science with the James Webb Space Telescope on solar system objects, even if the object is really very bright, like Jupiter, but also when you look at very faint things next to Jupiter," said Imke de Pater, professor emerita of astronomy and earth and planetary science at the University of California, Berkeley. De Pater and Thierry Fouchet from the Paris Observatory are co-principal investigators for the Early Release Science solar system observation team, one of 13 teams given early access to the telescope.
Samantha Trumbo, a 51 Pegasi b postdoctoral fellow at Cornell University, led the study of Ganymede, which was published July 21 in the journal Science Advances. Using measurements captured by the near infrared spectrometer (NIRSpec) on JWST, the team detected the absorption of light by hydrogen peroxide -- H2O2 -- around the north and south poles of the moon, a result of charged particles around Jupiter and Ganymede impacting the ice that blankets the moon.
"JWST revealing the presence of hydrogen peroxide at Ganymede's poles shows for the first time that charged particles funneled along Ganymede's magnetic field are preferentially altering the surface chemistry of its polar caps," Trumbo said.
The astronomers argue that the peroxide is produced by charged particles hitting the frozen water ice around the poles and breaking the water molecules into fragments -- a process called radiolysis -- which then recombine to form H2O2. They suspected that radiolysis would occur primarily around the poles on Ganymede because, unlike all other moons in our solar system, it has a magnetic field that directs charged particles toward the poles.
"Just like how Earth's magnetic field directs charged particles from the sun to the highest latitudes, causing the aurora, Ganymede's magnetic field does the same thing to charged particles from Jupiter's magnetosphere," she added. "Not only do these particles result in aurorae at Ganymede, as well, but they also impact the icy surface."
Trumbo and Michael Brown, professor of planetary astronomy at Caltech, where Trumbo recently received her Ph.D., had earlier studied hydrogen peroxide on Europa, another of Jupiter's four Galilean satellites. On Europa, however, the peroxide was detectable over much of the surface, perhaps, in part, because it has no magnetic field to protect the surface from the fast-moving particles zipping around Jupiter.
"This is likely a really important and widespread process," Trumbo said. "These observations of Ganymede provide a key window to understand how such water radiolysis might drive chemistry on icy bodies throughout the outer solar system, including on neighboring Europa and Callisto (the fourth Galilean moon)."
"It helps to actually understand how this so-called radiolysis works and that, indeed, it works as people expected, based on lab experiments on Earth," de Pater said.
Io's sulfurous environment
In a second paper, accepted for publication in the journal JGR: Planets, a publication of the American Geophysical Union, de Pater and her colleagues report new Webb observations of Io that show several ongoing eruptions, including a brightening at a volcanic complex called Loki Patera and an exceptionally bright eruption at Kanehekili Fluctus. Because Io is the only volcanically active moon in the solar system -- Jupiter's gravitational push and pull heats it up -- studies like this give planetary scientists a different perspective than can be obtained by studying volcanos on Earth.
For the first time, the researchers were able to link a volcanic eruption -- at Kanehekili Fluctus -- to a specific emission line, a so-called "forbidden" line, of the gas sulfur monoxide (SO).
Sulfur dioxide (SO2) is the main component of Io's atmosphere, coming from sublimation of SO2 ice, as well as ongoing volcanic eruptions, similar to the production of SO2 by volcanos on Earth. The volcanos also produce SO, which is much harder to detect than SO2. In particular, the forbidden SO emission line is very weak because SO is in such low concentrations and produced for only a short time after being excited. Moreover, the observations can only be made when Io is in Jupiter's shadow, when it is easier to see the glowing SO gases. When Io is in Jupiter's shadow, the SO2 gas in Io's atmosphere freezes out onto its surface, leaving only SO and newly emitted volcanic SO2 gas in the atmosphere.
"These observations with Webb show for the first time that the SO actually did come from a volcano," de Pater said.
De Pater had made previous observations of Io with the Keck Telescope in Hawaii and found low levels of the forbidden SO emission over much of the moon, but she was unable to tie SO hotspots specifically to an active volcano. She suspects that much of this SO, as well as the SO2 seen during an eclipse, is coming from so-called stealth volcanoes, which erupt gas but not dust, which would make them visible.
Twenty years ago, de Pater and her team proposed that this excited state of SO could only be produced in hot volcanic vents, and that the tenuous atmosphere allowed this state to stick around long enough -- a few seconds -- to emit the forbidden line. Normally, excited states that produce this emission are quickly damped out by collisions with other molecules in the atmosphere and never seen. Only in parts of the atmosphere where the gas is sparse do such excited states last long enough to emit forbidden lines. The greens and reds of Earth's auroras are produced by forbidden transitions of oxygen in the tenuous upper atmosphere.
"The link between SO and volcanoes ties in with a hypothesis we had in 2002 to explain how we could see SO emission at all," she said. "The only way we could explain this emission is if the SO is excited in the volcanic vent at a temperature of 1500 Kelvin or so, and that it comes out in this excited state, loses its photon within a few seconds, and that is the emission we see. So these observations are the first that actually show that this is the most likely mechanism of why we see that SO."
Webb will observe Io again in August with NIRSpec. The upcoming observation and the earlier one, which took place on Nov. 15, 2022, were taken when Io was in the shadow of Jupiter so that light reflected from the planet did not overwhelm the light coming from Io.
De Pater noted, too, that the brightening of Loki Patera was consistent with the observed period of eruptions at the volcano, which brighten, on average, about every 500 Earth days, with the brightening lasting for a couple of months. She determined this because it was not bright when she observed the moon with Keck in August and September 2022, nor was it bright when another astronomer observed it from April through July 2022. Only the JWST captured the event.
"The Webb observations showed that actually eruptions had started, and that it was much brighter than what we had seen in September," she said.
While De Pater is primarily focused on the Jovian system -- its rings, small moons and the larger moons Ganymede and Io -- she and other members of the early science team of some 80 astronomers are also using JWST to study the planetary systems of Saturn, Uranus and Neptune.
Story Source:
Journal Reference:
Cite This Page: | Chemistry and Material Sciences |
Planet formation is thought to be a messy process, as lots of growing planets end up in unstable orbits, resulting in large collisions like the one that resulted in the Moon's formation. The messiness may not end there, as many exosolar systems have indications that their planets migrated after their formation, creating the potential for further collisions. Again, there are indications that a similar thing happened in our own Solar System, as Jupiter and Saturn seem to have moved around before reaching their present orbits.
All the evidence for these collisions, however, is indirect or the product of modeling. Planetary migrations are too slow for us to track them, and we can't image planets that are close enough to their stars for collisions to be likely.
But a large team of scientists now think they have evidence of a smash-up of giant planets orbiting a Sun-like star. The evidence comes from a combination of two unusual events: the sudden brightening of the star at infrared wavelengths, followed over two years later by its dimming in the visual.
On and off
The star at issue, originally given the catchy name 2MASS J08152329-3859234, is distant and Sun-like, and even the authors of the new paper describe it as having been "otherwise unexceptional." (It was also known by the equally catchy Gaia DR3 5539970601632026752.) That changed in December 2021 when it was picked up by a program that identifies new supernovae by looking for sudden changes in the intensity of stars. The All Sky Automated Survey for Supernovae noticed that it had dimmed dramatically and gave it yet another name, ASASSN-21qj. We'll be using that one since it's by far the most concise option.
Dimming like that seen in ASASSN-21qj is unusual, but not unheard of—the past few years have seen astronomers excited by the sudden dimming of Betelgeuse, a nearby massive star. That event was eventually ascribed to a large cloud of dust, and similar explanations were offered for ASASSN-21qj by a paper published earlier this year. And large clouds of dust aren't so uncommon that they're exceptional.
But the team behind the new work, which was studying ASASSN-21qj as well, chanced upon something that did make it exceptional. They looked for images of the star that predated its sudden dimming and obtained some taken by NASA's Wide-field Infrared Survey Explorer. These showed that, about two and a half years before the dimming of ASASSN-21qj at optical wavelengths, it experienced a sudden brightening in the infrared. And that brightening lasted long enough that it was still going when the dimming event started.
Either of these events on their own is quite unusual. The fact that they both occurred to the same star would be extremely improbable, suggesting that the two events are likely to be connected. "Such a notable combination of observations," the team writes, "particularly the 2.5-year delay between the infrared and optical variation, requires an explanation." | Chemistry and Material Sciences |
Using an incredibly bright gamma-ray as a guide, the James Webb Space Telescope (JWST) has detected the heavy element tellurium around the site of a stellar-corpse collision. The discovery brings scientists a step closer to understanding where the universe's heaviest elements come from.
While scientists know that elements lighter than iron are forged in the hearts of massive stars, even the most massive stellar bodies aren't capable of generating hot and dense enough conditions at their cores to forge heavier elements such as gold, platinum or tellurium.
Neutron stars are created when stars can no longer perform nuclear fusion and collapse under their own gravity, creating matter so dense that a teaspoon of it would weigh 10 million tons (9 million metric tons). When neutron stars collide, this incredibly dense matter is sprayed into their immediate environment. This matter is rich in free neutrons, which can be captured by atoms, creating unstable atoms that eventually decay into elements with high numbers of protons and neutrons — the heavier elements in the periodic table. The decay of these elements also releases an explosion of electromagnetic radiation that astronomers see as a bright blast known as a kilonova.
"In the hunt for the heaviest elements, kilonovas are the main suspect," Darach Watson, an associate professor at the Niels Bohr Institute's Cosmic Dawn Center in Denmark, told Live Science.
However, the "smoking gun" evidence of this process has yet to be seen, partially because kilonovas are extremely rare. This discovery made with JWST brings researchers a tantalizing step closer to that evidence.
"In the one previous good set of data we have for a kilonova, we have discovered strontium and evidence for yttrium," Watson said. "But these are relatively light, with around 85 to 90 protons and neutrons."
Watson, who co-authored a paper detailing the findings published Oct. 25 in the journal Nature, explained that tellurium, with 128 protons and neutrons, gets scientists much closer to really heavy elements and pinpointing neutron-star mergers as the sites of heavy-element production.
"We would like to find elements closer to the heaviest elements, such as uranium, which has about 235 protons and neutrons," Watson said. "There is a very long way from around 90 to around 240.
Kilonova hunting
To take this important step and to make its first detection of a single element around a neutron star merger, JWST used the gamma-ray burst GRB 230307A, which was first detected by the Fermi Gamma-ray Space Telescope in March 2023. The emission was around 1,000 times brighter than the gamma-ray bursts that Fermi usually spots, lasted 200 seconds and seemed to be coming from a neutron-star collision, which was unusual because these events usually create much shorter-duration gamma-ray bursts.
Using an array of ground- and space-based telescopes, scientists detected the rough source of GRB 230307A in the sky. Observing the source in gamma-ray, X-ray, optical, infrared, and radio wave frequencies of light showed that the source was characteristic of a kilonova explosion.
During the later period of the explosion, as the kilonova light moved into the infrared, it became unobservable from Earth but an excellent target for JWST's highly-sensitive infrared detectors.
In addition to spotting the telltale emissions of tellurium, JWST pinpointed a spiral galaxy 120,000 light-years from the kilonova where the dead stars likely originated. The team suspects the neutron stars involved in the merger that created the kilonova were ejected from this galaxy as a binary pair and traveled a distance equal to the width of the Milky Way together, before finally spiraling together and merging.
Watson believes the detection of this heavy element around the neutron star merger wouldn't have been possible without JWST, the most powerful telescope humanity has ever put into space.
"Nothing else even gets close to the JWST!" he said. "The sensitivity of JWST is just amazing, and at these wavelengths, it is completely unparalleled. I mean, we knew in principle what it could do, but I think everybody was unprepared for this."
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Robert Lea is a science journalist in the U.K. who specializes in science, space, physics, astronomy, astrophysics, cosmology, quantum mechanics and technology. Rob's articles have been published in Physics World, New Scientist, Astronomy Magazine, All About Space and ZME Science. He also writes about science communication for Elsevier and the European Journal of Physics. Rob holds a bachelor of science degree in physics and astronomy from the U.K.’s Open University | Chemistry and Material Sciences |
In the beginning, galaxies were lacking in chemical and metal abundances, according to a team of astronomers that recently used a telescope to study the ancient universe.
Though the galaxies in the quarter-billion years seemed to follow the rules established by younger, previously observed galaxies regarding star formation rate and stellar mass, they had only a quarter the chemical abundance that was expected, the researchers found. The team’s research on the ancient galaxies was published last week in Nature Astronomy.
“It was like the galaxies had a rulebook that they followed—but astonishingly, this cosmic rulebook, appears to have undergone a dramatic rewrite during the universe’s infancy,” said study co-author Claudia Lagos, an astronomer at the International Centre for Radio Astronomy Research (ICRAR) and the Cosmic Dawn Center in Copenhagen in a University of Western Australia release.
The telescope was—of course—the Webb Space Telescope, a $10 billion space observatory launched to space in December 2021 and which has been making scientific observations since July 2022. Webb observes the cosmos at infrared and near-infrared wavelengths, which makes it an ideal tool for studying the most ancient light we can see.
The farther out in the universe a telescope looks, the more the light it sees has been stretched (or “shifted”) to the redder side of the electromagnetic spectrum. Thus, in the parlance of astronomers, the light has been “redshifted.” This stretching is assigned a number, which scientists call “z.” The bigger the “z” number, the farther away (and thus, the older) the object is.
Until recently, the team noted, galaxies’ chemical abundances could only be reliably measured at redshifts of z=3.3 or less. But Webb allowed the recent team to measure such abundances at redshifts of z=7-10, or between 500 million years and 750 million years after the Big Bang.
The researchers used Webb’s far-reaching gaze to measure the rates of star formation, stellar masses, and chemical abundances of galaxies from the universe’s first few hundred million years of existence.
“The most surprising discovery was that ancient galaxies produced far fewer heavy elements than we would have predicted based on what we know from galaxies that formed later,” Lagos said. “The early galaxies continually received new, pristine gas from their surroundings, with the gas influx diluting the heavy elements inside the galaxies, making them less concentrated.”
The ancient galaxies aren’t even the most ancient Webb has seen. Last November the telescope spotted two galaxies with redshifts of approximately 10.25 and 12.5, rivalling the age of Maisie’s Galaxy, another galaxy spotted by Webb with a redshift of 11.8, or an age of about 13.4 billion years. Our universe is about 13.77 billion years old.
One of Webb’s main tasks is scrutinizing these ancient galaxies, to understand how they took form and evolved. Many of the ancient galaxies Webb has seen appear surprisingly mature, given their appearance in a nascent universe.
But the new research indicates the galaxies still have their secrets—in this case, an evident lack of heavy elements. More observations by Webb could help explain how these galaxies took shape, but expect more mysteries to arise on scientists’ search for clarity. | Chemistry and Material Sciences |
When the asteroid Psyche has its first close-up with a NASA spacecraft, scientists hypothesize they will find a metal-rich asteroid. It could be part or all of the iron-rich interior of a planetesimal, an early planetary building block, that was stripped of its outer rocky shell as it repeatedly collided with other large bodies during the early formation of the solar system.
New research from scientists at NASA’s Ames Research Center in California’s Silicon Valley suggests that is exactly what the agency’s Psyche mission will find.
Led by Anicia Arredondo, the paper’s first author and a postdoctoral researcher at the Southwest Research Institute in San Antonio, Texas, and Maggie McAdam, Ames research scientist and principal investigator, the team observed Psyche in Feb. 2022 using NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA). The now-retired observatory was a Boeing 747SP aircraft modified to carry a reflecting telescope. As a flying telescope, SOFIA collected data that was not affected by Earth’s lower atmosphere and made observations from all over the world, including over the oceans.
For the first time, SOFIA was able to gather data from every part of Psyche’s surface. It also allowed the team to collect data about the materials that make up Psyche’s surface – information that could not be gathered from ground-based telescopes.
The Ames team studied the way different wavelengths of light bounce off Psyche. Researchers used a mid-infrared camera, which detects wavelengths in the middle of the electromagnetic spectrum, to observe the asteroid. They measured its emissivity(the amount of energy it radiates) and porosity (how many tiny holes or spaces an object has). Both characteristics can provide clues about the materials that make up an object.
The team observed that Psyche’s emissivity data was mostly flat, meaning there were no spikes or other notable features in its spectra – that is, a chart or a graph that shows the intensity of light the asteroid emits over a range of energies. Similarly flat spectra have been found in laboratory settings when mid-infrared instruments are used on metal objects. This led the researchers to conclude that Psyche is likely a metallic body.
Notably, the team did not observe a spectral feature called the 10-micron plateau, which typically indicates a “fluffy” surface, like lunar regolith. Previous studies of Psyche had observed this feature, which suggests there may be differences between the surface at Psyche’s north pole, which was facing the Earth at the time of the Ames team’s study, and the surface at its south pole, which was the focus of previous studies. The team also proposed that the south pole regolith observed by other researchers could have been ejected from a collision elsewhere on Psyche’s surface. This idea is supported by past observations of Psyche, which found evidence of huge depressions and impact craters across the asteroid.
“With this analysis and the previous studies of Psyche, we have reached the limit of what astronomical observations can teach us about this fascinating asteroid,” said McAdam. “Now we need to physically visit Psyche to study it up close and learn more about what appears to be a very unique planetary body.” NASA’s mission to Psyche will provide that opportunity. The spacecraft is set to launch on Oct. 12, 2023. It will arrive at the asteroid in 2029 and orbit it for at least 26 months.
Psyche’s potential to answer many questions about planet formation is a key reason why it was selected for close observation by a spacecraft. Scientists believe that planets like Earth, Mars, and Mercury have metallic cores, but they are buried too far below the planets’ mantles and crusts to see or measure directly. If Psyche is confirmed to be a planetary core, it can help scientists understand what is inside the Earth and other large planetary bodies.
Psyche’s size is also important for advancing scientific understanding of Earth-like planets. It is the largest M-type (metallic) asteroid in our solar system and is long enough to cover the distance from New York City to Baltimore, Maryland. This means Psyche is more likely to show differentiation, which is when the materials inside a planet separate from one another, with the heaviest materials sinking to the middle and forming cores.
“Every time a new study of Psyche is published, it raises more questions,” said Arredondo, who was a postdoctoral researcher at Ames on the SOFIA mission when the Psyche observations were collected. “Our findings suggest the asteroid is very complex and likely holds many other surprises. The possibility of the unexpected is one of the most exciting parts of a mission to study an unexplored body, and we look forward to gaining a more detailed understanding of Psyche’s origins.”
More about the Psyche and SOFIA missions:
Arizona State University leads the Psyche mission. A division of Caltech in Pasadena, JPL is responsible for the mission’s overall management, system engineering, integration and test, and mission operations. Maxar Technologies in Palo Alto, California, provided the high-power solar electric propulsion spacecraft chassis.
Psyche is the 14th mission selected as part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. NASA’s Launch Services Program, based at Kennedy, is managing the launch service.
SOFIA was a joint project of NASA and the German Space Agency at DLR. DLR provided the telescope, scheduled aircraft maintenance, and other support for the mission. NASA’s Ames Research Center in California’s Silicon Valley managed the SOFIA program, science, and mission operations in cooperation with the Universities Space Research Association, headquartered in Columbia, Maryland, and the German SOFIA Institute at the University of Stuttgart. The aircraft was maintained and operated by NASA’s Armstrong Flight Research Center Building 703, in Palmdale, California. SOFIA achieved full operational capability in 2014 and concluded its final science flight on Sept. 29, 2022.
For news media:
Members of the news media interested in covering this topic should reach out to the Ames newsroom. | Chemistry and Material Sciences |
The Webb Space Telescope recently turned its focus to a nearby exoplanet and found that it may be a Hycean world, or a world completely covered in a single global ocean, and with a hydrogen atmosphere. And what’s more, the telescope detected a possible detection—note, possible detection, of dimethyl sulfide, a molecule only known to be produced on Earth by living organisms.
The exoplanet is K2-18 b, a world nearly nine times Earth’s size orbiting a star some 120 light-years from Earth. Webb has observed signs of water vapor on exoplanets before, but never an exoplanet that looks to be covered in water oceans.
Webb—launched in December 2021 and taking scientific data of the cosmos since July 2022—did not discover the exoplanet; it was first spotted in 2015 by NASA’s K2 mission.
K2-18 b lies in its star’s habitable zone, meaning the world is at the distance from its star necessary for liquid water to persist on the exoplanet’s surface. Since water is necessary for life as we know it, it is the primary hurdle for exoplanets to meet the our current sensibilities as to what’s meant by habitable. Another hurdle is the exoplanet’s temperature; it’s possible that K2-18 b is too hot for any of its oceans to sustain life, or even be liquid, according to a NASA release.
In its benchmark decadal survey on astronomy and astrophysics, the National Academies of Sciences, Engineering, and Medicine stressed the importance of finding habitable worlds. Webb is a crucial part of that search and NASA has already drawn up plans for the still-juvenile Webb’s successor in that search, the Habitable Worlds Observatory. But that mission won’t launch for at least a decade, leaving Webb (and the Hubble Space Telescope, Webb’s still-operational predecessor) to do plenty of exoplanetary legwork.
Hubble observed the recently observed exoplanet back in 2019 and found signs that the planet’s atmosphere contained water vapor. The Webb observations go a step further. The telescope’s Near-Infrared Imager and Slitless Spectrograph (NIRISS) and Near-Infrared Spectrograph (NIRSpec) instruments took spectra of K2-18 b, by seeing how much starlight was impeded in the exoplanet’s atmosphere as it passed in front of its star.
Webb discerned the presence of carbon-bearing molecules like methane and carbon dioxide, but little ammonia, on the planet. That chemical composition suggests that K2-18 b may contain a water ocean beneath its hydrogen atmosphere. Analysis of the candidate Hycean world is hosted on the preprint server arXiv and is accepted for publication in The Astrophysical Journal Letters.
“Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere,” said Nikku Madhusudhan, an astronomer at the University of Cambridge and the study’s lead author, in the NASA release. “Traditionally, the search for life on exoplanets has focused primarily on smaller rocky planets, but the larger Hycean worlds are significantly more conducive to atmospheric observations.”
Webb also detected what looked like dimethyl sulfide (DMS) in the planet’s atmosphere. On Earth, dimethyl sulfide is produced by living things, and most of our planet’s atmospheric DMS is produced by marine phytoplankton. “Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2-18 b at significant levels,” Madhusudhan added.
Madhusudhan added that the data collected by Webb in just two observations of K2-18 b are equivalent to eight observations done with Hubble, thanks to the newer space observatory’s sensitivity and the range of wavelengths at which it observes.
Follow-up observations of the Hycean candidate will be conducted using Webb’s Mid-Infrared Instrument, or MIRI. While the detection of dimethyl sulfide is very tentative, K2-18 b is increasingly showing signs it is a water world with potential—if not for astrobiological reasons, for better understanding the types of habitable worlds in our nearby universe. | Chemistry and Material Sciences |
Wedged between the orbits of Mars and Jupiter, the main asteroid belt contains over 1 million rocky objects, but perhaps few of them are as intriguing as Psyche. The metal-rich asteroid might have once been an ancient planetary building block that was stripped of its outer rocky shell as our solar system came to be. What remains of Psyche may hold the answers as to how Earth and its neighboring planets were formed, and a namesake mission is on the case to probe the asteroid for clues.
NASA is getting ready to launch its Psyche spacecraft to rendezvous with the main belt asteroid in an effort to uncover the origin story of Earth. Previous asteroid-probing missions have explored space rocks made of rock or ice, so this is scientists’ first chance to get up close with a metal-rich asteroid which could suggest a different narrative for the formation of the solar system.
Here’s what you need to know about the mission.
The Psyche mission is set for launch on October 12 at 10:16 a.m. ET.
The spacecraft will liftoff on board a SpaceX Falcon Heavy rocket from Launch Complex 39A at NASA’s Kennedy Space Center in Florida.
A week before its original launch date on October 5, engineers discovered an issue with the Psyche spacecraft’s thrusters that could have caused it to overheat during its eight-year mission. As a result, the mission’s liftoff date was delayed by one week as the team resolved the issue.
Psyche will travel around 2.2 billion miles to reach the main asteroid belt. If all goes well, the spacecraft will enter asteroid Psyche’s orbit in late July 2029 and begin its mission in August of the same year.
It will spend about two years orbiting the asteroid to take pictures, map the surface, and collect data in order to determine Psyche’s composition.
Psyche is a 173-mile-wide (280-kilometer-wide) asteroid that orbits the Sun in the outer part of the main asteroid belt between Mars and Jupiter. It was discovered in 1852 and named after the Greek goddess of the soul.
This odd-looking, potato-like space rock might be an exposed core of a planetesimal, or an early planetary building block. Psyche may have been stripped of its outer layer due to violent collisions that took place during the early formation of the solar system.
Since we can’t drill our way to Earth’s core, visiting the Psyche asteroid is the next best thing as it offers scientists a rare look at the center of our planet and other rocky planets like it. It could also hold clues to the violent history of our solar system, and how planets like our own came to be in the midst of the chaos.
Analysis of radar observations of the asteroid indicates that Psyche is likely made of a mixture of rock and metal, with metal composing 30% to 60% of its volume, according to NASA.
The Psyche spacecraft is about the size of a small van. It’s packed with a magnetometer, a gamma-ray and neutron spectrometer, and a multispectral imager to study the asteroid.
Based on data obtained by Earth-based radar and optical telescopes, Psyche appears to have two large craters, as well as significant variation in its metal content and color across the asteroid’s surface, according to NASA. Observing the asteroid up close will allow us to confirm Psyche’s battle scars and offer more insight into its origin. The mission expects to receive its first images around two months after launch.
The spacecraft’s magnetometer will look for evidence of an ancient magnetic field, which would support the theory that Psyche is the leftover core of a planetary body. The gamma-ray and neutron spectrometer will help determine the chemical elements that make up the asteroid, while the multispectral imager will provide information about the mineral composition of Psyche.
The Psyche mission cost an estimated $1.2 billion, SpaceNews reported earlier in September. The probe was originally supposed to launch in 2022, but NASA delayed it due to issues with the spacecraft’s flight software and testing equipment that could not be resolved in time for liftoff. The mission had to wait a year for the next launch window that would place it on a trajectory towards the asteroid.
In October 2022, NASA announced that Psyche was back on track for launch after an internal review that looked into staffing and communication issues that contributed to its delay.
Another mission, however, suffered the consequences. NASA’s long-awaited VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) mission to Venus was delayed indefinitely as the space agency reallocated its resources elsewhere. | Chemistry and Material Sciences |
Scientists have found carbon dioxide (CO2) on Europa, Jupiter's fourth-largest moon, for the first time.
The chemical compound, which is famously abundant on Earth, was detected by NASA's James Webb Space Telescope on the moon's frozen surface.
It may have originated from the vast ocean that's thought to exist beneath its icy shell, which suggests it could have been produced by lifeforms.
CO2 is known as one of the key building blocks of life because it is the primary source of carbon for all living things, at least on our planet.
Europa is described as one of the few locations in our solar system with liquid water, along with Earth and Saturn's moon Enceladus, making it a target of interest for astrobiologists.
If there is life under the moon's surface shell – which is thought to be around 10 miles thick – it may be adapted to survive in extremely frigid temperatures.
These lifeforms could be tiny, such as 'extremophile' microbes that would be invisible to the naked human eye.
Researchers have published their new results in two separate studies in the journal Science.
'On Earth, life likes chemical diversity – the more diversity, the better,' said Geronimo Villanueva of NASA's Goddard Space Flight Center in Greenbelt, Maryland
'Understanding the chemistry of Europa’s ocean will help us determine whether it’s hostile to life as we know it, or whether it might be a good place for life.'
Scientists are almost certain that hidden beneath the icy surface of Europa is a saltwater ocean with about twice as much water as Earth’s global ocean.
But determining whether this concealed ocean has the right chemical elements to support life has been difficult.
To find an answer, the US researchers used data from the Webb telescope's near-infrared spectrometer (NIRSpec) to map CO2 on the surface of Europa.
NIRSpec can measure the near-infrared spectrum of more than 100 objects at once to reveal more about its properties, including temperature, mass and chemical composition.
The most CO2 was in a 1,800 kilometer-wide (1,120 mile) area called Tara Regio, where there is a lot of 'chaos terrain' – areas with jagged ridges and cracks.
The disrupted surface ice suggests there has been an exchange of material between the subsurface ocean and this icy outside shell.
Exactly what creates chaos terrain is not well understood, but one theory is that warm water from the ocean rises up to melt the surface ice, which then re-freezes over time into new uneven crags.
The scientists don't think the CO2 came from somewhere other than the ocean below – by hitching a ride on a meteorite that crashed into the moon, for example.
But the researchers can't rule out that carbon came up from the planet's interior as rock-like carbonate minerals, which irradiation could then have broken apart to become CO2.
Samantha Trumbo, a planetary scientist at Cornell University and the study's lead author, told AFP that the carbon was 'ultimately derived from the interior, likely the internal ocean'.
Previous observations from the Hubble Space Telescope, the predecessor of James Webb, show evidence for ocean-derived salt in Tara Regio.
This makes the area significantly more yellow than the rest of Europa's scarred white plains
The experts had also hoped to find plumes of water or volatile gases shooting out of the moon's surface, but failed to spot any.
Ultimately, determining for sure what's beneath Europa’s icy layer may require a satellite to land on the moon and drill through it.
However, scientists may be able to learn some basic things about the ocean’s composition before 'we drill through the ice to get the full picture', said Villanueva.
Two major space missions plan to get a closer look at Europa and its mysterious ocean, although both are orbiters meaning they won't land on it.
The European Space Agency's Jupiter moon probe Juice launched in April, while NASA's Europa Clipper mission is scheduled to blast off in October 2024. | Chemistry and Material Sciences |
A major milestone and new results from NASA’s Parker Solar Probe were announced on Dec. 14 in a press conference at the 2021 American Geophysical Union Fall Meeting in New Orleans. The results have been published in Physical Review Letters and accepted for publication in the Astrophysical Journal.
For the first time in history, a spacecraft has touched the Sun. NASA’s Parker Solar Probe has now flown through the Sun’s upper atmosphere – the corona – and sampled particles and magnetic fields there.
The new milestone marks one major step for Parker Solar Probe and one giant leap for solar science. Just as landing on the Moon allowed scientists to understand how it was formed, touching the very stuff the Sun is made of will help scientists uncover critical information about our closest star and its influence on the solar system.
“Parker Solar Probe “touching the Sun” is a monumental moment for solar science and a truly remarkable feat,” said Thomas Zurbuchen, the associate administrator for the Science Mission Directorate at NASA Headquarters in Washington. “Not only does this milestone provide us with deeper insights into our Sun’s evolution and its impacts on our solar system, but everything we learn about our own star also teaches us more about stars in the rest of the universe.”
As it circles closer to the solar surface, Parker is making new discoveries that other spacecraft were too far away to see, including from within the solar wind – the flow of particles from the Sun that can influence us at Earth. In 2019, Parker discovered that magnetic zig-zag structures in the solar wind, called switchbacks, are plentiful close to the Sun. But how and where they form remained a mystery. Halving the distance to the Sun since then, Parker Solar Probe has now passed close enough to identify one place where they originate: the solar surface.
The first passage through the corona – and the promise of more flybys to come – will continue to provide data on phenomena that are impossible to study from afar.
“Flying so close to the Sun, Parker Solar Probe now senses conditions in the magnetically dominated layer of the solar atmosphere – the corona – that we never could before,” said Nour Raouafi, the Parker project scientist at the Johns Hopkins Applied Physics Laboratory in Laurel, Maryland. “We see evidence of being in the corona in magnetic field data, solar wind data, and visually in images. We can actually see the spacecraft flying through coronal structures that can be observed during a total solar eclipse.”
Closer Than Ever Before
Parker Solar Probe launched in 2018 to explore the mysteries of the Sun by traveling closer to it than any spacecraft before. Three years after launch and decades after first conception, Parker has finally arrived.
Unlike Earth, the Sun doesn’t have a solid surface. But it does have a superheated atmosphere, made of solar material bound to the Sun by gravity and magnetic forces. As rising heat and pressure push that material away from the Sun, it reaches a point where gravity and magnetic fields are too weak to contain it.
That point, known as the Alfvén critical surface, marks the end of the solar atmosphere and beginning of the solar wind. Solar material with the energy to make it across that boundary becomes the solar wind, which drags the magnetic field of the Sun with it as it races across the solar system, to Earth and beyond. Importantly, beyond the Alfvén critical surface, the solar wind moves so fast that waves within the wind cannot ever travel fast enough to make it back to the Sun – severing their connection.
Until now, researchers were unsure exactly where the Alfvén critical surface lay. Based on remote images of the corona, estimates had put it somewhere between 10 to 20 solar radii from the surface of the Sun – 4.3 to 8.6 million miles. Parker’s spiral trajectory brings it slowly closer to the Sun and during the last few passes, the spacecraft was consistently below 20 solar radii (91 percent of Earth’s distance from the Sun), putting it in the position to cross the boundary – if the estimates were correct.
On April 28, 2021, during its eighth flyby of the Sun, Parker Solar Probe encountered the specific magnetic and particle conditions at 18.8 solar radii (around 8.1 million miles) above the solar surface that told scientists it had crossed the Alfvén critical surface for the first time and finally entered the solar atmosphere.
“We were fully expecting that, sooner or later, we would encounter the corona for at least a short duration of time,” said Justin Kasper, lead author on a new paper about the milestone published in Physical Review Letters, and deputy chief technology officer at BWX Technologies, Inc. and University of Michigan professor. “But it is very exciting that we’ve already reached it.”
Into the Eye of the Storm
During the flyby, Parker Solar Probe passed into and out of the corona several times. This is proved what some had predicted – that the Alfvén critical surface isn’t shaped like a smooth ball. Rather, it has spikes and valleys that wrinkle the surface. Discovering where these protrusions line up with solar activity coming from the surface can help scientists learn how events on the Sun affect the atmosphere and solar wind.
At one point, as Parker Solar Probe dipped to just beneath 15 solar radii (around 6.5 million miles) from the Sun’s surface, it transited a feature in the corona called a pseudostreamer. Pseudostreamers are massive structures that rise above the Sun’s surface and can be seen from Earth during solar eclipses.
Passing through the pseudostreamer was like flying into the eye of a storm. Inside the pseudostreamer, the conditions quieted, particles slowed, and number of switchbacks dropped – a dramatic change from the busy barrage of particles the spacecraft usually encounters in the solar wind.
For the first time, the spacecraft found itself in a region where the magnetic fields were strong enough to dominate the movement of particles there. These conditions were the definitive proof the spacecraft had passed the Alfvén critical surface and entered the solar atmosphere where magnetic fields shape the movement of everything in the region.
The first passage through the corona, which lasted only a few hours, is one of many planned for the mission. Parker will continue to spiral closer to the Sun, eventually reaching as close as 8.86 solar radii (3.83 million miles) from the surface. Upcoming flybys, the next of which is happening in January 2022, will likely bring Parker Solar Probe through the corona again.
“I’m excited to see what Parker finds as it repeatedly passes through the corona in the years to come,” said Nicola Fox, division director for the Heliophysics Division at NASA Headquarters. “The opportunity for new discoveries is boundless.”
The size of the corona is also driven by solar activity. As the Sun’s 11-year activity cycle – the solar cycle – ramps up, the outer edge of the corona will expand, giving Parker Solar Probe a greater chance of being inside the corona for longer periods of time.
“It is a really important region to get into because we think all sorts of physics potentially turn on,” Kasper said. “And now we’re getting into that region and hopefully going to start seeing some of these physics and behaviors.”
Narrowing Down Switchback Origins
Even before the first trips through the corona, some surprising physics was already surfacing. On recent solar encounters, Parker Solar Probe collected data pinpointing the origin of zig-zag-shaped structures in the solar wind, called switchbacks. The data showed one spot that switchbacks originate is at the visible surface of the Sun – the photosphere.
By the time it reaches Earth, 93 million miles away, the solar wind is an unrelenting headwind of particles and magnetic fields. But as it escapes the Sun, the solar wind is structured and patchy. In the mid-1990s, the NASA-European Space Agency mission Ulysses flew over the Sun’s poles and discovered a handful of bizarre S-shaped kinks in the solar wind’s magnetic field lines, which detoured charged particles on a zig-zag path as they escaped the Sun. For decades, scientists thought these occasional switchbacks were oddities confined to the Sun’s polar regions.
In 2019, at 34 solar radii from the Sun, Parker discovered that switchbacks were not rare, but common in the solar wind. This renewed interest in the features and raised new questions: Where were they coming from? Were they forged at the surface of the Sun, or shaped by some process kinking magnetic fields in the solar atmosphere?
The new findings, in press at the Astrophysical Journal, finally confirm one origin point is near the solar surface.
The clues came as Parker orbited closer to the Sun on its sixth flyby, less than 25 solar radii out. Data showed switchbacks occur in patches and have a higher percentage of helium – known to come from the photosphere – than other elements. The switchbacks’ origins were further narrowed when the scientists found the patches aligned with magnetic funnels that emerge from the photosphere between convection cell structures called supergranules.
In addition to being the birthplace of switchbacks, the scientists think the magnetic funnels might be where one component of the solar wind originates. The solar wind comes in two different varieties – fast and slow – and the funnels could be where some particles in the fast solar wind come from.
“The structure of the regions with switchbacks matches up with a small magnetic funnel structure at the base of the corona,” said Stuart Bale, professor at the University of California, Berkeley, and lead author on the new switchbacks paper. “This is what we expect from some theories, and this pinpoints a source for the solar wind itself.”
Understanding where and how the components of the fast solar wind emerge, and if they’re linked to switchbacks, could help scientists answer a longstanding solar mystery: how the corona is heated to millions of degrees, far hotter than the solar surface below.
While the new findings locate where switchbacks are made, the scientists can’t yet confirm how they’re formed. One theory suggests they might be created by waves of plasma that roll through the region like ocean surf. Another contends they’re made by an explosive process known as magnetic reconnection, which is thought to occur at the boundaries where the magnetic funnels come together.
“My instinct is, as we go deeper into the mission and lower and closer to the Sun, we’re going to learn more about how magnetic funnels are connected to the switchbacks,” Bale said. “And hopefully resolve the question of what process makes them.”
Now that researchers know what to look for, Parker’s closer passes may reveal even more clues about switchbacks and other solar phenomena. The data to come will allow scientists a glimpse into a region that’s critical for superheating the corona and pushing the solar wind to supersonic speeds. Such measurements from the corona will be critical for understanding and forecasting extreme space weather events that can disrupt telecommunications and damage satellites around Earth.
“It’s really exciting to see our advanced technologies succeed in taking Parker Solar Probe closer to the Sun than we’ve ever been, and to be able to return such amazing science,” said Joseph Smith, Parker program executive at NASA Headquarters. “We look forward to seeing what else the mission discovers as it ventures even closer in the coming years.”
Parker Solar Probe is part of NASA’s Living with a Star program to explore aspects of the Sun-Earth system that directly affect life and society. The Living with a Star program is managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland, for NASA’s Science Mission Directorate in Washington. The Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, manages the Parker Solar Probe mission for NASA and designed, built, and operates the spacecraft.
Related Links
- Learn more about Parker Solar Probe
- Switchbacks Science: Explaining Parker Solar Probe’s Magnetic Puzzle
- NASA’s Parker Solar Probe Sheds New Light on the Sun
- NASA’s Parker Solar Probe and the Curious Case of the Hot Corona
- NASA Scientist Kelly Korreck on the Journey to the Sun, and What It Takes to Get There | Chemistry and Material Sciences |
NASA completed its first-ever sample return mission from an asteroid today, with a science capsule containing material from an asteroid landing after having traveled on a 1.2 billion-mile journey from the asteroid Bennu. The capsule was released from the OSIRIS-REx spacecraft as it passed by Earth this morning, entering the atmosphere at around 27,000 mph.
The OSIRIS-REx mission, launched in 2016, has collected as much as several hundred grams of asteroid material, which could help scientists understand the earliest stages of the solar system.
“NASA invests in small body missions like OSIRIS-REx to investigate the rich population of asteroids in our solar system that can give us clues about how the solar system formed and evolved,” said Melissa Morris, OSIRIS-REx program executive, in a mission overview briefing. “It’s our own origin story.”
The capsule was released from the OSIRIS-REx spacecraft as it passed by Earth this morning
The science capsule was slowed by parachutes and landed in the Department of Defense’s Utah Test and Training Range at 10:52 AM ET, a landing area chosen as it is the largest restricted airspace in the United States and has been used for previous NASA sample return missions like Genesis and Stardust.
The landing area is 36 miles by 8.5 miles, and the entire mission has required a very high level of precision — particularly for the spacecraft to rendezvous with the asteroid and collect its sample in 2020.
“The really precise navigation required to orbit Bennu and to touch down and collect our sample, we were under a meter away from our target,” Sandra Freund, OSIRIS-REx program manager, said in a pre-landing briefing. “So that illustrates what kind of navigation precision we’ve had throughout this mission.”
Recovery teams collected the sample from the Utah desert, with a helicopter carrying the sample taking off at 12:15 PM ET. The capsule will be taken to a temporary clean room for first disassembly, removing some of the larger parts such as the backshell. It will then undergo a process called a nitrogen purge in which nitrogen is pumped into the canister to protect the sample. This prevents any of Earth’s atmosphere from entering it as it is shipped to Johnson Space Center in Houston, Texas, where the canister will be opened for the first time so the sample can be analyzed.
Why do we need an asteroid sample?
“We’re really interested in trace organic molecular chemistry,” Dante Lauretta, OSIRIS-REx principal investigator, told The Verge. “We really want to understand — the things that are used in biology today, like amino acids that make proteins and nucleic acids that make up our genes — were they formed in ancient asteroid bodies and delivered to the Earth from outer space?”
If you’re not familiar with models of the formation of the solar system, that idea might sound outlandish, bordering on fantastical. But it’s actually a fairly well-supported and widely accepted theory for how some of the key elements for life came to be on Earth.
It’s important to be clear that the theory is not that life itself arose elsewhere and was delivered to Earth, but rather that the basic building blocks of life — often referred to as organic compounds — could have arrived here billions of years ago carried by asteroids.
That’s been a theory for decades; but to test it out, scientists need access to asteroidal material. Going to visit an asteroid and using instruments on a spacecraft to study it is a good start, but to do the kind of detailed analysis scientists want requires a much bigger laboratory, equipped with instruments like a mile-wide type of particle accelerator called a synchrotron which would be impossible to fit onto a spacecraft.
“were they formed in ancient asteroid bodies and delivered to the Earth from outer space?”
Another option is to study meteorites, which are pieces of matter (including from asteroids) that come from space and fall to Earth’s surface. That’s how most of this research has been performed historically, using these tiny fragments as samples.
But there are two problems with this approach. Firstly, when a meteorite falls, it doesn’t have the context of where in the solar system it came from. Researchers can’t know its origin, or see what other bodies it was close to, which can give important clues to the interpretation of any data. And secondly, by the time a meteorite has passed through Earth’s atmosphere and landed, it may have picked up matter along the way and been contaminated by the local environment.
When scientists are looking for these trace organic compounds, they need to know that anything they find comes from space and wasn’t picked up here on Earth. So to do that, they need an asteroid sample that is as pristine as possible. That’s where OSIRIS-REx comes in.
A worldwide effort
The OSIRIS-REx mission is the first time that NASA has brought back a sample from an asteroid, but it is following in the footsteps of the Japanese space agency JAXA, which collected two asteroid samples in its historic Hayabusa and Hayabusa 2 missions. Though the first Hayabusa mission gathered just a tiny amount of material, the second mission managed to return around five grams of material from asteroid Ryugu in 2020.
OSIRIS-REx is returning much more material from asteroid Bennu, at around 250 grams, which means that more science can be done — particularly when looking for those small amounts of trace materials. But researchers see the two missions as complementary, rather than competitive.
“Not all asteroids are the same,” said Lauretta, who is also a member of the Hayabusa 2 team. Both Ryugu and Bennu have a similar spinning-top-like shape, but they look very different. Ryugu is larger and more red in color, while Bennu is smaller and more blue. Scientists still aren’t sure what that difference in color means, but being able to analyze and compare the samples on Earth should help understand both how the asteroids are similar and how they differ.
“We look at this as not two sample analysis programs, but one big sample analysis program,” Lauretta said, “because it’s a worldwide effort.”
A window into the early solar system
When scientists want to understand how the Earth formed, they need to look beyond our planet and out into the solar system. Star systems form from enormous clouds of gas that collapse into a star at the center, spinning a disk of material around it.
That’s clear from looking at other star systems, but there’s also evidence from our own solar system: the planets revolve around the sun in the same direction and in a single plane, supporting the idea they formed from a single disk of material.Some of that material coalesced into planets, and some was swept into the earliest asteroids, a number of which still exist today.
When scientists want to understand how the Earth formed, they need to look beyond our planet and out into the solar system
In fact, the estimates we have for the age of the solar system come from dating grains within meteorites that have fallen to Earth. That’s because Earth has factors like erosion and plate tectonics which recycle rocks and wipe away the earliest history of the planet, meaning the oldest rocks we have ever found here are around 4 billion years old. The material from asteroids, however, can be even older.
“The asteroids date from about 500 million years earlier in time than the oldest rocks on Earth. So as a geologist, I want to go back all the way to the beginning,” Lauretta said. “And the fun thing is, when you’re looking at asteroids you go literally to the very beginning of the solar system.”
Bennu, the asteroid from which OSIRIS-REx collected its sample, is thought to be made up of material that is around 4.5 billion years old, making it a potential time capsule from the earliest stages of the solar system. But researchers can’t know its age for sure until a detailed analysis has been performed.
A new asteroid target
Now that the OSIRIS-REx spacecraft has dropped off the capsule containing the sample, its initial job is over. But the spacecraft is still in space, and even though it can’t collect another sample it does still have power and a propulsion system, and all its science instruments still operating.
So rather than waste this craft, it will become OSIRIS-APEX and go on to study a new target, the asteroid Apophis. By a fortunate chance of orbital dynamics, it will be able to rendezvous with this asteroid — one of the most famous in the solar system, because it will come close to Earth in the next few years — and study it.
“In 2029, in April, Apophis is gonna fly within 30,000 kilometers of the surface of the Earth, which is about the altitude that our weather satellites orbit at,” Lauretta said. “It’s the biggest, closest flyby of an asteroid for a thousand years,” and it may even be visible to the naked eye from some locations on Earth.
OSIRIS-APEX will be able to follow the asteroid’s path around Earth and meet it, to perform more science observations.
As for the sample from asteroid Bennu, that will be taken to a special facility at NASA’s Johnson Space Center in Houston, where work can begin to understand the chemistry of this precious commodity.
Getting the sample back to Earth is just the beginning of the science research, and the team is anxiously awaiting this culmination of all their efforts.
“I get to be one of the very first people on earth to see the capsule, as it is in position out there in the desert. It’s going to be quite an emotional moment for me,” Lauretta said. “We’ve been building and testing and designing this thing for over 12 years. So it’s the end of a very, very long journey, and the beginning of the next chapter.” | Chemistry and Material Sciences |
An unusual cannon found underwater off the coast of Sweden in 2001 may be the oldest shipboard gun ever discovered in Europe, a new study finds.
Pieces of cloth found inside the object — thought to be the remains of a bag for gunpowder known as a cartouche — have been radiocarbon-dated to the 14th century, making the cannon one of the earliest of its kind and possibly the oldest shipboard cannon in Europe on record.
The analysis also revealed that the weapon was charged and ready for use, meaning it wasn't just being transported for use on land.
Rather than shooting metal cannonballs, the early cannon was designed to fire balls of rock against attackers, said study lead author Staffan von Arbin, a doctoral student in maritime archaeology at the University of Gothenburg in Sweden.
"This type of early cannon most definitely fired stone shots," von Arbin told Live Science in an email. "The intention was not to sink an enemy vessel. These guns were 'anti-personnel' weapons — they were simply used to 'clear the deck' of an enemy vessel."
The authors of the study, published Aug. 3 in the journal The Mariner's Mirror, don't know if the early cannon was fitted to a merchant vessel or a warship, but they hope to solve the mystery by exploring the underwater location where it was discovered.
Early cannon
The cannon was found at a depth of about 60 feet (20 meters) and about 3 miles (5 kilometers) southwest of the island of Marstrand on Sweden's west coast.
The archaeologists suggest that the cannon came from a ship that had foundered at the location, possibly after hitting the skerry — a low rock — of Kleningen, which is a few hundred feet to the south. But they also acknowledged that it could have been accidentally dropped or thrown overboard from a ship in distress.
The cannon is almost 19 inches (47.5 centimeters) long and roughly funnel-shaped, with a narrow powder chamber at the back and a wide barrel measuring more than 7 inches (18.5 cm) across at the front. Other cannons of this type were fitted with a wooden gun carriage so they could be aimed.
Von Arbin said such funnel-shaped cannons were the first type used in Europe after the technology was introduced there in the 13th century, probably via the Middle East. The exact reason for the distinctive shape is not known, but it may have had something to do with the way they were loaded.
Copper alloy
The researchers also examined the cannon's metal body with inductively coupled plasma mass spectrometry (ICP-MS), a technique that ionizes a tiny sample of a substance with a high-temperature plasma and analyzes the resulting gas.
They were expecting the cannon to be made of gunmetal, which is a bronze made from copper and tin with significant amounts of zinc and nickel to make it more durable. Instead, they found that it was made of a copper alloy with relatively small amounts of tin and high amounts of lead, which would have made it relatively brittle.
The researchers noted this alloy was unsuitable for gun-making, and they suspect it was used because better alloys were not known at that time.
Von Arbin noted that the Baltic was heavily trafficked by trading ships in the 14th century and that merchant vessels were often armed against pirates and the ships of enemy nations.
The location where the cannon was found is very exposed, and any shipwreck there is probably broken up, he said. However, he hopes that an analysis of the seafloor could find some remains of the cannon and that more dates and the origins of the ship could be revealed by dendrochronology, a technique that examines tree growth rings in wood to determine when and where it grew.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Tom Metcalfe is a freelance journalist and regular Live Science contributor who is based in London in the United Kingdom. Tom writes mainly about science, space, archaeology, the Earth and the oceans. He has also written for the BBC, NBC News, National Geographic, Scientific American, Air & Space, and many others. | Chemistry and Material Sciences |
Sept. 24 was a big day for NASA, when an orange-and-white capsule containing pieces of an asteroid landed on Earth, charred from its ultrahigh-speed fall through our atmosphere. The asteroid in question, named Bennu, is thought to have been roaming space since the early days of our solar system — meaning these samples could reveal to us what our cosmic neighborhood looked like way before we got here.
Shot into space as part of the agency's OSIRIS-REx mission in 2016, the capsule was enclosed for years within a spacecraft that made a 4-billion-mile-long journey to reach Bennu. Once on the asteroid's surface, it then extended an arm that briefly touched down on the rock in order to retrieve a little bit of its material.
The hope, scientists had said, was to collect at least 60 grams of Bennu's material — and, on Monday (Oct. 23), the OSIRIS-REx team announced the mighty spacecraft managed to retrieve far more. Far. More.
According to a NASA blog post, the curation team that's been processing the samples says it has removed and collected 70.3 grams (2.48 ounces) of Bennu material from the capsule so far — and it hasn't even actually been opened yet. Those 70.3 grams come from just the area on the outside (and part of the inside) of the sample collector's head.
"The sample processed so far includes the rocks and dust found on the outside of the sampler head, as well as a portion of the bulk sample from inside the head, which was accessed through the head’s mylar flap," the post states. "Additional material remaining inside the sampler head, called the Touch-and-Go Sample Acquisition Mechanism, or TAGSAM, is set for removal later, adding to the mass total."
Even though OSIRIS-REx isn't the first asteroid-sample-return mission humanity has completed — JAXA's Hayabusa takes that title — it is the heftiest. Or, in other words, the capsule that landed in September delivered the largest-ever asteroid sample to our planet,
The agency has said it will give 25% of the Bennu bits to over 200 scientists at 25 different facilities, 4% to the Canadian Space Agency and 0.5% to JAXA. (NASA received about 10% of the Hayabusa 1 asteroid payload from a space rock named Itokawa.) The remaining approximately 70%, the team says, will be stored at Johnson Space Center to be studied for years to come, much like Apollo moon rock samples continue to be investigated decades after being brought to Earth by astronauts.
Part of the reason there is so much of the Bennu sample within this capsule actually has to do with the touch-and-go process itself. When the OSIRIS-REx sample collection mechanism dipped toward the rock to gather a few asteroid pieces, scientists watching were surprised to see Bennu wasn't a nice, solid object like you might expect. No, it was kind of malleable; when the sample collection arm made contact with the rock, shrouds of dust particles were released into the air, causing quite a scene and almost swallowing the spacecraft.
This is also why scientists still aren't sure exactly how much sample is in the OSIRIS-REx capsule in general. We'll only know when the container is finally opened up. Next, the team will start tackling how to perform that task— but, according to the blog post, that might prove slightly difficult.
"After multiple attempts at removal, the team discovered two of the 35 fasteners on the TAGSAM head could not be removed with the current tools approved for use in the OSIRIS-REx glovebox," it says. "The team has been working to develop and implement new approaches to extract the material inside the head, while continuing to keep the sample safe and pristine."
Basically, the OSIRIS-REx scientists have many regulations in place for how to deal with the sample because it's very important they don't interfere with its preservation. For instance, the blog post says, all curation work is performed inside a special glove box that has a constant flow of nitrogen. Without that flow, the sample might be exposed to Earth's atmosphere.
"While the procedure to access the final portion of the material is being developed," the post continues, "the team has removed the TAGSAM head from the active flow of nitrogen in the glovebox and stored it in its transfer container, sealed with an O-ring and surrounded by a sealed Teflon bag to make sure the sample is kept safe in a stable, nitrogen-rich, environment." | Chemistry and Material Sciences |
A new X-ray telescope showed how star explosion shockwaves align powerful magnetic fields able to accelerate atom fragments close to the speed of light.
The finding was revealed at the remnant of a supernova, or star explosion, called SN 1006. It was scrutinized by NASA's and the Italian Space Agency's Imaging X-ray Polarimetry Explorer (IXPE). The space telescope, which launched in December 2021, measured the supernova's high-energy X-rays.
The remnant is the remains of a type Ia supernova. This type produces explosions either when two white dwarfs or old star cores collide, or when a white dwarf accrued too much mass from a companion star.
The explosion in 1006 that produced SN 1006 was witnessed in what the International Astronomical Union now calls the constellation of Lupus, the wolf. It was seen as far afield as the Arab world, as well as in locations that are now part of modern-day China, Europe and Japan.
The supernova is also believed to have been the brightest in recorded history. Located 6,500 light years away, the supernova was so bright it remained visible in the night sky to the unaided eye for three years, according to ancient records.
IXPE showed that the X-ray light is polarized — that is, the X-ray photons oscillate or vibrate in a preferred direction — by magnetic fields that are orientated in a certain way, within the expanding supernova's remnant of gas and dust.
"Now we can see that SN 1006's magnetic fields are turbulent, but also present an organized direction," lead researcher Ping Zhou, of Nanjing University in Jiangsu, China, said in an Oct. 26 NASA statement.
Understanding the order and orientation of magnetic fields in a supernova remnant is crucial because such remnants are believed to be the origin of at least some cosmic rays. These rays are charged particles such as protons, electrons and some ions that were accelerated to nearly the speed of light by intense magnetic fields in the supernova.
Many scientists suspect cosmic rays come from supernovas, but the rays' exact origins have been difficult to pin down. Past observations of SN 1006, NASA officials added in the statement, suggest supernova remnants like it may act as a particle accelerator, and that the surrounding nebula (or gas cloud) may be where cosmic rays originate.
IXPE's findings now suggest the magnetic fields in the supernova are aligned so that the fields are pointing away from the source of the supernova's explosion. Two other supernova remnants investigated by IXPE — which are Cassiopeia A (whose light likely reached Earth in the 1660s) and a supernova remnant spotted by Danish astronomer Tycho Brahe in 1572 — also display evidence for magnetic fields oriented radially outwards.
The X-rays from SN 1006, however, are significantly more polarized, providing much more compelling evidence for the magnetic field phenomenon than the other two supernovas considered in the study.
"The polarization properties obtained from our spectral-polarimetric analysis align remarkably well with outcomes from other methods and X-ray observatories," stated Yi-Jung Yang of the University of Hong Kong, who is a co-author of the research.
As the supernova shockwave propagates through the gas and dust surrounding the supernova, the study found, the magnetic fields become aligned with the direction of the shockwave. Charged particles are swept up by the shockwave, become trapped in the magnetic field lines, and are accelerated.
Those cosmic rays then travel through space, breaching the area of the sun's influence (the heliospheric bubble) around the solar system that is blown by the solar wind, or the charged particles that stream out from our sun.
The rays next arrive at Earth, where during the last leg of their journey they crash into atmospheric molecules. Each collision causes the molecule to shatter in an air shower of short-lived muons, which are "daughter particles" (decay products after a molecule disintegrates). The muons swiftly decay in a flash of light that is then picked up by cosmic ray detectors, capturing the echoes of stars that died centuries ago.
The findings were published Oct. 27 in The Astrophysical Journal. | Chemistry and Material Sciences |
A SpaceX rocket recently punched a hole in Earth's upper atmosphere while venturing into space, leaving behind a blood-red streak of light in the sky similar to an aurora.
The Falcon 9 rocket, which was carrying 15 SpaceX Starlink satellites into orbit, lifted off from Vandenberg Space Force Base in California on July 19 at around 9 p.m. PDT, according to Live Science's sister site Space.com. As the rocket rose into the upper atmosphere, its exhaust plume became illuminated by sunlight, which created a stunning spectacle seen across California and parts of Arizona. But what followed was even more awe-inspiring.
"After the rocket passed overhead, a red fluorescent glow expanded southward and crossed over with the Milky Way [in the sky]," Jeremy Perez, a photographer based in Flagstaff, Arizona, told Spaceweather.com. Perez captured several epic shots of the "fluorescent red glow" from his vantage point at the San Francisco Volcanic Fields, located north of Flagstaff. The light show lasted around 20 minutes, he added.
The unusual red light was the result of the rocket disrupting the ionosphere, the part of Earth's atmosphere where gases are ionized, or lose electrons, and turn into plasma. The ionosphere stretches between roughly 50 and 400 miles (80 and 644 kilometers) above Earth's surface, according to NASA. This is a previously known phenomenon, but the latest episode is one of the most vivid examples to date, Spaceweather.com reported.
"Ionospheric holes" are created when a rocket's second stage burns fuel between 124 and 186 miles (200 and 300 km) above Earth's surface, Jeffrey Baumgardner, a physicist at Boston University, told Spaceweather.com. At this height, the carbon dioxide and water vapor from the rocket's exhaust cause ionized oxygen atoms to recombine, or form back into normal oxygen molecules, which excites the molecules and causes them to emit energy in the form of light, he added.
This is similar to how auroras form, except the dancing lights are caused by solar radiation heating up gases rather than recombining them. The holes pose no threat to people on the surface and naturally close up within a few hours as the recombined gases get re-ionized.
Scientists have known that rockets can trigger these sorts of effects since at least 2005, when a Titan rocket triggered "severe ionospheric perturbations" that were equivalent to a minor geomagnetic storm. But they are becoming more common.
In August 2017, a Falcon 9 rocket created a hole four times bigger than the state of California, the largest ever recorded. And in June 2022, another Falcon 9 punched a hole over the U.S. East Coast, sparking a display of red lights from New York to the Carolinas that many observers mistook for the northern lights, Spaceweather.com reported at the time.
As the number of rocket launches, particularly by private companies such as SpaceX, continues to increase in the coming years, it is likely that these ionospheric holes and their associated light shows will become much more common, according to Spaceweather.com.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Harry is a U.K.-based staff writer at Live Science. He studied Marine Biology at the University of Exeter (Penryn campus) and after graduating started his own blog site "Marine Madness," which he continues to run with other ocean enthusiasts. He is also interested in evolution, climate change, robots, space exploration, environmental conservation and anything that's been fossilized. When not at work he can be found watching sci-fi films, playing old Pokemon games or running (probably slower than he'd like). | Chemistry and Material Sciences |
Active black holes alter their galaxies' chemical distributionActive supermassive black holes can considerably influence the presence and distribution of chemical molecules in their host galaxies.Mrigakshi Dixit| Sep 18, 2023 10:13 AM ESTCreated: Sep 18, 2023 10:13 AM ESTscienceGet a daily digest of the latest news in tech, science, and technology, delivered right to your mailbox. Subscribe now.By subscribing, you agree to our Terms of Use and Policies You may unsubscribe at any time.The colossal black holes exert a complex and dynamic array of effects on their host galaxies, and astronomers continue to deepen their understanding of these phenomena.According to a new study, active supermassive black holes can considerably influence the presence and distribution of chemical molecules in their host galaxies.A team of scientists from the National Astronomical Observatory of Japan and Nagoya University evaluated the data collected by a robust network of telescopes: the Atacama Large Millimeter/Subsillimeter Array (ALMA) in Chile. Mapping the distribution of the molecules Studying the surroundings of a black hole is a highly challenging task. Given the black holes’ tremendou distance from Earth, measuring the chemical composition distribution of the gas around it is even more difficult. See Also Related Active black holes alter their galaxies' chemical distribution Astronomers detect most luminous transient event linked to black hole New research sheds light on the way black hole mergers are formed Advanced facilities such as ALMA are required to see the galactic core, which is frequently obscured by thick stellar dust and gas. ALMA comprises 66 radio telescopes that work together to provide extraordinary observational capabilities.In this study, ALMA focused on the central region of NGC 1068 (also known as M77), a barred spiral galaxy about 47 million light-years away in the direction of the constellation Cetus. The team combined the power of ALMA’s high spatial resolution and a new machine-learning analysis technique to map the distribution of molecules across two central regions of this galaxy. They discovered 23 different chemical molecule distributions in this galaxy. “This is the first survey to objectively depict the distribution of all detected molecules through unbiased observations,” noted the official release. The release further added: “The results show that along the path of the bipolar jets emanating near the black hole, molecules commonly found in galaxies such as carbon monoxide (CO) seem to break down, while the concentrations of distinctive molecules such as an isomer of HCN and the cyanide radical (CN) increase.”Schematic diagram illustrating the location of the bipolar jet and galactic disk emanating from the supermassive black hole at the galaxy’s center, along with the resulting outflow of molecular gasALMA (ESO/NAOJ/NRAO), T. Saito et al. The supermassive black hole lurking at the center of this galaxy emits powerful polar jets that appear to impact the chemical composition.This latest observation serves as compelling proof that supermassive black holes influence the overall structure and the chemical distribution of the galaxies they inhabit.Moreover, this new study is vital to understanding the evolution of galaxies. The findings were reported in The Astrophysical Journal. Study abstract: We present an imaging molecular line survey in the 3 mm band (85–114 GHz) focused on one of the nearest galaxies with an active galactic nucleus (AGN), NGC 1068, based on observations taken with the Atacama Large Millimeter/submillimeter Array. 23 molecular transitions are obtained in the central ∼3 kpc region, including the circumnuclear disk (CND) and starburst ring (SBR) with 60 and 350 pc resolution. The column densities and relative abundances of all the detected molecules are estimated under the assumption of local thermodynamic equilibrium in the CND and SBR. Then, we discuss the physical and chemical effects of the AGN on molecular abundance corresponding to the observation scale. We found that H13CN, SiO, HCN, and H13CO+are abundant in the CND relative to the SBR. In contrast, 13CO is more abundant in the SBR. Based on the calculated column density ratios of N(HCN)/N(HCO+), N(HCN)/N(CN), and other molecular distributions, we conclude that the enhancement of HCN in the CND may be due to high-temperature environments resulting from strong shocks, which are traced by the SiO emission. Moreover, the abundance of CN in the CND is significantly lower than the expected value of the model calculations in the region affected by strong radiation. The expected strong X-ray irradiation from the AGN has a relatively lower impact on the molecular abundance in the CND than mechanical feedback. HomeScienceAdd Interesting Engineering to your Google News feed.Add Interesting Engineering to your Google News feed.SHOW COMMENT (1) For You Missing USMC F-35B debris field has finally been foundAn aha! moment in infants reveals the origin of agency in humansManganese ocean ‘potatos’ are highly radioactiveGiorgio Rosa, the engineer who built his own islandPredictions for what the world will be like in 2100?Chinese researchers create dancing microrobots using lasersStudy finds Neanderthal gene increases severe COVID riskStudy: MXene versatile material successfully mass-produced'Mysterious' beach crater turns out to be hole dug by locals12 science, tech, and engineering newsletters you need to check out Job Board | Chemistry and Material Sciences |
Discovery of oldest 3D-preserved microorganisms
For the first time ever, researchers have been able to study the form of microorganisms from the early days of evolution some 1.5 billion years ago. These microorganisms are of exceptional importance for our understanding of the development of early life.
Researchers from Technische Universität Berlin, the National Academy of Sciences of Ukraine, the Museum of Natural History Berlin and the National Museum of Natural History in Luxembourg have discovered the oldest, three-dimensionally preserved microfossils on Earth to date on minerals from the Volyn quartz mine near the city of Zhytomyr (Ukraine). The findings are published in the journal Biogeosciences.
Their original form was preserved by a micrometer-thin layer of aluminum silicate, which could only form as a result of a special set of geological circumstances. Most of previous evidence of Precambrian microorganisms was based on indirect methods such as characteristic imprints in the rock or the detection of biological degradation products.
"It's fascinating that here, for the first time, we are able to study the fossils of primordial microorganisms under a scanning electron microscope. We were actually looking to study beryl and topaz from the mine. What we have found now is far more valuable than any gemstones," explains Professor Emeritus Dr. Gerhard Franz of the Institute of Applied Geosciences at TU Berlin.
This is because the finds are the first fossilized microorganisms dating back to what is referred to as the "boring billion," the first seemingly uneventful billion years before the Precambrian Revolution. "Only then, about 600 million years ago, did evolution produce skeletons made of calcium carbonate or phosphate; invertebrates such as clams, corals or snails emerged, and then vertebrates with backbones. Real fossils with preservable skeletons only became possible as a result of this biomineralization."
Because living organisms had no skeletons more than 600 million years ago, they could not actually preserve their form—which is why very little is known about this period. It was mainly only in sedimentary rocks, i.e., former deposits on sea floors, that carbon remains of the microorganisms were preserved, which were then destroyed by millions of years of mechanical deformation. And it is only because life forms prefer the lighter carbon isotope 12C to the heavier variant 13C that it has been possible to speculate at all that this was once biological material.
It is only recently that researchers found for the first time biological compounds such as cholesterol in rocks in Australia, that are 1.5 billion years old and that directly suggest primordial life forms. In other rocks, the early microorganisms have left only faint imprints, from which it is difficult to discern their form.
The first images of primordial microorganisms: Filaments, spheres and tentacles
"What we are looking at now under our electron microscope are mostly fibrous structures. Either thin filaments that branch out, or thick ones that have small protrusions or dents," Franz explains. The thickness of the objects varies between 10 and 200 micrometers and their length is up to several millimeters, sometimes with a thin channel in the middle.
This means these primordial microorganisms can also be seen with the naked eye. What is particularly exciting is that the researchers also found a few previously unknown forms of microorganisms. These had shell or spherical-shaped structures or tentacle-like branches.
Some of the fossilized organisms resemble fungi
"By analyzing the carbon isotopes 12C and 13C, we have also been able to prove that our finds must once have been living creatures," Franz explains. The age of the finds was measured using a special isotope method, which resulted in a minimum age for the fossils of 1.5 billion years. The researchers also detected the substance chitosan in certain filamentous objects using infrared spectroscopy, as well as the elements bismuth and tellurium using an electron microscope.
"This all points to a fungus-like organism," Franz says. However, that would only apply to some of the finds, he adds. "From the other fossilized microorganisms, we can at least assume that they must have been single or multicellular organisms with distinct cell structures." These probably lived with the fungi in a common ecosystem.
Subterranean life preserved by a geyser
The location of the fossilized primordial microorganisms on granite rock in a quartz mine suggests both their way of life and the reasons for their exceptionally good state of preservation. "Even today, microorganisms live up to three kilometers deep in the Earth's crust," Franz explains. They live there—without sunlight—on substances such as phosphorus, nitrogen or carbon dioxide, some of which are dissolved in water and migrate downward from above through fissures and crevices or are already present there.
The microorganisms obtain the energy they need for their metabolism from chemical processes on minerals. In the granite caverns of the Volyn quartz mine, such colonies of microorganisms were apparently already present near the Earth's surface 1.5 billion years ago. And because granite contains a lot of fluorine, strongly corrosive hydrofluoric acid was formed underground in interaction with water and heat, which dissolved a lot of aluminum and silicon.
Like a geyser, this solution shot into the caverns from time to time, covering the microorganisms with a micrometer-thin layer of aluminum silicate. "Of course, the microorganisms died as a result—but they were also perfectly preserved," says Franz.
The history of the finds
"As is so often the case in science, the history of our find owes a lot to coincidence," he reports. "The main reason my predecessor, Professor Klaus Langer, initiated the cooperation with Ukraine back in the days of perestroika was to support researchers in the still young, independent Ukraine. The interesting gemstone finds in the Volyn quartz mine came as a nice surprise for the working group."
When Franz started out as the new head of the academic chair years later, he one day detected some strange fibers on the beryls when examining them under an electron microscope. Over the years, and with the help of rock samples from different museums, that's how the discovery got rolling.
"Nevertheless, today we are only at the beginning. Further investigations and possibly new finds will be able to tell us even more about the primordial microorganisms, especially about previously unknown forms on the continents, and not just in the sea," says Franz.
This could provide new insights into the early development of life on Earth, but perhaps also into the development of life under extreme conditions on other planets.
More information: Gerhard Franz et al, The Volyn biota (Ukraine)—indications of 1.5 Gyr old eukaryotes in 3D preservation, a spotlight on the "boring billion, Biogeosciences (2023). DOI: 10.5194/bg-20-1901-2023
Gerhard Franz et al, Fossilization of Precambrian microfossils in the Volyn pegmatite, Ukraine, Biogeosciences (2022). DOI: 10.5194/bg-19-1795-2022
Journal information: Biogeosciences
Provided by Technische Universität Berlin | Chemistry and Material Sciences |
The cars, cellphones, computers and televisions that people in the U.S. use every day require metals like copper, cobalt and platinum to build. Demand from the electronics industry for these metals is only rising, and companies are constantly searching for new places on Earth to mine them.
Scientists estimate that lots of these metals exist thousands of miles beneath Earth’s surface, in its molten core, but that’s far too deep and hot to mine. Instead, some companies hope to one day search for deposits that are literally out of this world — on asteroids.
The commercialization of asteroid mining is still a ways off, but in October 2023, NASA launched a scientific mission to explore the metal-rich asteroid Psyche. The main goal of the mission is studying the composition and structure of this asteroid, which could tell scientists more about Earth’s core since the two objects might have a similar makeup.
Both likely contain platinum, nickel, iron and possibly even gold – materials of commercial interest.
I am a planetary geologist whose work explores other planets and astronomical objects like Mars, Venus and the Moon. I will be following the Psyche mission closely, as this is the first time that scientists will be able to learn about the composition and structure of a possible piece of a planetary core similar to the Earth’s, without indirect seismic or magnetic measurements, or replicating the pressure and temperature conditions of the Earth’s core in our labs.
With the spacecraft estimated to arrive at the asteroid’s orbit in 2029, the findings from the Psyche mission will provide unique insights into the type of metals present on the asteroid’s surface, as well as their amount, and the minerals containing these metals. This data is essential both for scientists like me exploring the formation and evolution planetary bodies, as well as for companies investigating the possibility of asteroid mining.
Asteroid formation
Asteroids come in a variety of sizes. Some are the size of a town, while others are the size of a state. Most asteroids are made of rocks and represent the leftovers from the early formation of our solar system around 4.6 billion years ago.
Not every asteroid is the same – some, like Bennu, the target of NASA’s OSIRIS-REx mission, are rich in carbon. These are very old, and they will teach scientists more about how planets formed and how life may have begun on Earth.
Others, like Psyche, are made of metals and potentially result from one or more collisions between astronomical objects when the solar system was forming. These collisions left debris flying through space — including potential pieces of a planet’s metal-rich core. A NASA spacecraft will orbit and analyze the surface of Psyche.
Mining in space
Not every mineral deposit on Earth is mineable. Companies first look for deposits with a high level of metal purity. They also investigate how affordable and feasible extracting the metal would be before choosing where to mine.
Similarly, before mining an asteroid, companies will have to think about all those factors, and they’ll have to come up with the infrastructure needed to mine at a distance and transport the metals they mine hundreds of millions of miles back to Earth. The technology to do that is still years away, and transporting metals would require major funding.
A few companies around the world have already started to think about what the best and lowest cost approach would be, drawing from processes similar to those used on Earth.
The first step would be finding a mineable metal deposit. Next, they’d drill and extract the metals on the asteroid. One of the most important differences with Earth mines is that each step would be undertaken remotely with spacecrafts orbiting around the asteroid and robots landing on its surface. Then, a spacecraft would send the resulting materials back to Earth.
Asteroid mining plans are still at their earliest stages. A few companies like Planetary Resources and Deep Space Industries, with goals to extract metals from space, were acquired by other companies.
Experts can’t quite tell yet how acquiring valuable metals from asteroids would affect the global economy, but these metals could potentially flood the market and lower their values.
The Psyche mission is a huge step in figuring out what sort of metals are out there, and it may also answer questions about the composition and properties of Earth’s core. | Chemistry and Material Sciences |
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
Astronomers have made a first-of-its-kind discovery — a white dwarf star with two completely different faces.
White dwarfs are burnt remains of dead stars. Our sun will become a white dwarf in about 5 billion years after it swells into a red giant star, blows out its outer material and, with only the core left, shrinks back into a blinding white-hot remnant.
The newly discovered white dwarf has two sides, one made of hydrogen and the other made of helium. Researchers have nicknamed the star Janus, for the Roman god of transition, which has two faces. A study detailing the findings was published July 19 in the journal Nature.
“The surface of the white dwarf completely changes from one side to the other,” said lead study author Ilaria Caiazzo, a postdoctoral scholar research associate in astronomy at the California Institute of Technology, in a statement. “When I show the observations to people, they are blown away.”
White dwarfs are incredibly dense, compressing a mass comparable to our sun’s into something equivalent to an Earth-size planet.
The strong gravitational influence at play during the death of a star means that the remaining heavy elements move toward the center while lighter elements like hydrogen or helium rise to the upper layer. Given the blazing temperatures of white dwarfs, the hottest ones have hydrogen atmospheres. As the stars cool over time, they tend to have helium atmospheres.
But typical white dwarfs don’t have one side of the star devoted to one element, and the other dominated by another.
The unusual stellar remnant was first detected by the Zwicky Transient Facility, located at Caltech’s Palomar Observatory. Caiazzo used the instrument, which scans the skies each night, for a recent survey of highly magnetized white dwarfs when an object appeared that rapidly changed in brightness.
Follow-up observations were conducted by Caiazzo and her team using Palomar’s CHIMERA instrument, the HiPERCAM located on the Gran Telescopio Canarias in Spain’s Canary Islands and W.M. Keck Observatory on Maunakea in Hawaii.
The three observatories showed that Janus was rotating on its axis every 15 minutes — and showcased the star’s double-faced nature and composition. Astronomers used a spectrometer to separate the light of the white dwarf into different wavelengths, which revealed the chemical signature of hydrogen on one side and helium on the other.
The star has a scorching temperature of 62,540 degrees Fahrenheit (34,726 degrees Celsius), which researchers determined with help from the Neil Gehrels Swift Observatory.
How Janus formed two faces
The researchers aren’t quite sure why the star has two completely different sides. It’s possible that Janus is experiencing a rare form of evolution.
“Not all, but some white dwarfs transition from being hydrogen- to helium-dominated on their surface,” Caiazzo said. “We might have possibly caught one such white dwarf in the act.”
As the white dwarf cools over time, the heavier and lighter materials may mix together. During this transition, it’s possible for hydrogen to become diluted within the interior, allowing helium to become the dominant element.
If this is occurring on Janus, one side of the star is evolving before the other side.
“Magnetic fields around cosmic bodies tend to be asymmetric, or stronger on one side,” Caiazzo said. “Magnetic fields can prevent the mixing of materials. So, if the magnetic field is stronger on one side, then that side would have less mixing and thus more hydrogen.”
Another possibility is that the magnetic fields are shifting the pressure and density of these atmospheric gases on Janus.
“The magnetic fields may lead to lower gas pressures in the atmosphere, and this may allow a hydrogen ‘ocean’ to form where the magnetic fields are strongest,” said study coauthor James Fuller, professor of theoretical astrophysics at Caltech, in a statement. “We don’t know which of these theories are correct, but we can’t think of any other way to explain the asymmetric sides without magnetic fields.”
The team will continue the search for more white dwarfs like Janus using the Zwicky Transient Facility because the instrument is “very good at finding strange objects,” Caiazzo said. | Chemistry and Material Sciences |
New research has revealed how supermassive black holes that lurk at the hearts of large galaxies influence the distribution of chemicals throughout their entire galactic homes.
Scientists have long understood that supermassive black holes have a massive influence on the galaxies around them. In particular, as these black holes feed from matter surrounding them, they form electromagnetic radiation emissions that are bright enough to outshine the combined light of every star in their home galaxy. This active feeding process also causes jets of matter to blast outwards from the black hole at near the speed of light.
Combined, these phenomena deem the galactic heart an active galactic nucleus (AGN) and heat gas and dust as well as push star-forming matter away from the region, which can limit star births and, thus, inhibit growth of the galaxy itself. However, scientists don’t understand as clearly how the distribution of chemicals in galaxies is influenced by AGNs and their supermassive black hole engines.
The new research was conducted by a team of astronomers that used the Atacama Large Millimeter/submillimeter Array (ALMA) to look at the supermassive-powered AGN of the galaxy NGC 1068, also known as Messier 77 (M77) or simply, the "Squid Galaxy." In particular, the researchers were interested in parsing the distribution of chemicals around the bright heart of this barred spiral galaxy, located 51.4 light-years away from Earth, in the constellation Cetus. The black hole associated with this AGN is shrouded by a thick ring of dust called circumnuclear disk and surrounded by a region of intense star birth called the starburst ring.
"Recently, an important and interesting issue about galaxies has been the investigation of power sources in active galaxies, focusing especially on the obscured galactic nuclei, which are the central engines of the galaxy starburst or AGN," the team behind the research writes in a paper published in the Astrophysical Journal. "Observations revealing the power sources may provide key information regarding the evolution of galaxies. The chemistry-based approach, which involves the use of line surveys in galaxies, is an effective way of solving this problem."
Thanks to the impressive spatial resolution ability of ALMA and the employment of a new machine learning technique, the team was able to map the distribution of 23 molecules present in the galaxy.
This is possible because chemical elements and compounds absorb light at characteristic wavelengths, so by looking at light shining through gas and dust, scientists can see "lines," or gaps, where light has been absorbed. This shows the chemical composition of the dust and gas.
In particular, the team observed that isotopes of hydrogen cyanide were confined to the central region of the AGN, while cyanide radicals were also located at the galaxy’s active center but blasted outwards too, in jets extending from both poles of the supermassive black hole.
The researchers also spotted that, unlike these two molecules, carbon monoxide isotopes — common in galaxies — steered clear of the central region.
To the team, this is clear evidence of supermassive black holes affecting not just the large-scale structure of galaxies but also their chemical composition. The research delivered some surprises for the researchers, too, with the team finding that high-energy X-rays from the AGN had less of an impact on chemical distribution than theorized.
"The abundance of cyanide in the circumnuclear disk is significantly lower than the expected value of the model calculations in the region affected by strong radiation," the authors concluded. "The expected strong X-ray irradiation from the AGN has a relatively lower impact on the molecular abundance in the circumnuclear disk than mechanical feedback."
A paper on this research was published Sept. 14 in The Astrophysical Journal | Chemistry and Material Sciences |
NASA journeys to the metal-rich asteroid Psyche
It's a world like no other: a metal-rich asteroid that could be the remnants of a small planet, or perhaps an entirely new type of celestial body unknown to science.
A NASA spacecraft blasted off from the Kennedy Space Center Friday bound for Psyche, an object 2.2 billion miles (3.6 billion kilometers) away that could offer clues about the interior of planets like Earth.
"We're going to learn all kinds of new things, how these things fly through the solar system, and they hit each other and they cause the evolution of what we have today, our solar system," NASA chief Bill Nelson said shortly before lift off at 10:19 am Eastern Time (1419 GMT) on a reusable SpaceX Falcon Heavy rocket.
"We've visited either in person or robotically worlds made of rock, worlds made of ice and worlds made of gas... but this will be our first time visiting a world that has a metal surface," lead scientist Lindy Elkins-Tanton told reporters during a briefing this week.
Trailing a blue glow from its next-generation electric propulsion system and flanked by two large solar arrays, the van-sized probe should arrive at its destination in the Asteroid Belt, between Mars and Jupiter, in July 2029.
Studying cores of rocky planets
Over the course of two years, it will deploy its suite of advanced instruments to probe Psyche for evidence of an ancient magnetic field and to study its chemical and mineral composition, as well as topography.
Scientists think Psyche, named after the goddess of the soul in Greek mythology, could be part of the iron-nickel core of a "planetesimal," a building block of all rocky planets, that was left exposed after an ancient collision blasted off the exterior.
It could also be something else—a primordial solar system object that's never been documented before.
"This is our one way to see a core," said Elkins-Tanton. "We say tongue in cheek that we're going to outer space to explore inner space."
Psyche is thought to have an irregular, potato-like shape, measuring 173 miles (280 kilometers) across at its widest point—though it's never actually been seen up close.
Until recently, scientists thought it was overwhelmingly composed of metal—but analyses based on reflected radar and light now indicate that metal probably comprises between 30-60 percent, with the rest being rock.
Solar electric propulsion
The mission will include several technological innovations.
The Psyche spacecraft, named after the asteroid, will test out next generation communications based on lasers—a step NASA compares to upgrading old telephone lines on Earth to fiber optics.
Deep Space Optical Communications, as the system is called, "was designed to demonstrate 10 to 100 times the data-return capacity of state-of-the-art radio systems used in space today," said Abi Biswas of NASA's Jet Propulsion Laboratory in a statement.
Psyche also uses a special kind of propulsion system called "Hall-effect thrusters" that harnesses the energy from solar panels to create electric and magnetic fields that, in turn, expel charged atoms of xenon gas.
The thrust it exerts is roughly equal to the weight of an AA battery in your hand. But in the void of space, the spacecraft will accelerate continuously to tens of thousands of miles per hour.
Such systems avoid the need to carry thousands of pounds of chemical fuel into space, and Psyche will be the first time they are used beyond lunar orbit.
© 2023 AFP | Chemistry and Material Sciences |
As humanity teeters on the brink of World War III, a doctor has shared a morbid guide about surviving nuclear fallout.
Abud Bakri MD, a residency physician in California, combed through mountains of research papers to see how the US handled previous threats to create the ultimate survival guide for a looming nuclear fallout.
He concluded there are three acute survival concepts: distance from a nuclear blast, time exposed to radiation and proper shielding.
Bakri also warned that people with lean bodies may want to increase their body fat now, as food could be scarce after the first bombs drop.
There are at least 12,500 nuclear warheads worldwide.
Paul Gambles, co-founder of MBMG Group, told Bloomberg that we are closer to World War III now than we have ever been in the past.
Russia invaded Ukraine in 2022, which saw the US swiftly respond to Ukraine's aid.
The two Eastern nations have been at war since 2014, but the recent invasion was the most significant attack on a European country since World War II.
In addition, fighting in the Middle East has also been reignited after Hamas' deadly terrorist attack on Israel.
Bakri shared his guide on X, explaining he analyzed data from the Federal Emergency Management Agency (FEMA), World Health Organization (WHO) and the US federal government.
'This is what I'm going to do to try and save my family. [This is] general information [and] not medical advice, he shared.
Consuming more calories is crucial for survival
While most medical professionals tell people to steer clear of processed food, Bakri said people will want to stock up in the event of a nuclear fallout.
This is because food may be scarce, and people want to consume as many calories as possible to survive.
According to the US government website Ready, canned foods, dry mixes and other items that do not need refrigeration, cooking or water are ideal for disasters.
The website shared several foods to have on hand: canned meats, fruits, and vegetables; protein or fruit bars, dry cereal or granola; peanut butter; dried fruit; canned juices; and non-perishable pasteurized milk.
Bakri also noted that fasting could occur.
He shared that each pound of fat you have equals one and a half days of energy.
'Might be wise to be adapted from now as the first few days will be BRUTAL Might be wise to not be TOO LEAN (fit influencers with five percent [body fat] will not have enough calories to survive),' Bakri posted.
Bakri also suggested that people should have battery-powered or hand-crank radios due to the electromagnetic pulses from the blast knocking out all electronics
Your distance from the blast zone could mean life or death
Bakri shared: 'Just like in real estate, the key to survival is location, location, location.'
When a nuclear bomb makes an impact, it sends a shockwave that can extend about half of a mile from the target.
Thermal damage can extend about one mile, flying debris can travel up to a few miles and radiation from the blast could reach people within three-fourths of a mile from the explosion site.
According to the US Department of Health and Human Services, radioactive fallout occurs in an irregular elliptical pattern in the direction the wind blows, and lethal radiation could extend up to six miles.
Bakri also highlighted the fact that there are certain hotspots where enemies will likely attack first.
The hotspots in the US are home to intercontinental ballistic missile silos, which are located in five states: Colorado, Wyoming, Nebraska, Montana, and North Dakota.
The US government deliberately set up these sites during the Cold War with the former Soviet Union - in the event of an attack, bombs would fall on sparsely populated areas.
These areas were known as 'Nuclear Sponge' states to be sacrificed.
A map originally released by the Natural Resources Defense Council in 2002 shows potential nuclear targets in the US.
The map shows potential targets in every state, with dense clusters along the eastern seaboard and California.
Large clusters are highlighted in Colorado, Montana, North Dakota and Wyoming.
There are around 90 active nuclear plants, typical targets, in the US, including plants in Alabama, Arizona, Maryland, New Jersey, Pennsylvania and Tennessee.
The map suggests the safest real estate is in parts of Idaho, Maine, northern California, and Oregon, where the lack of nuclear plants and more sparse populations make them less likely targets.
Every second counts after the blast
'Radiation is highest and most deadly immediately, but these nuclear isotopes are not stable and rapidly degrade,' shared Bakri,
'The more time insulation away from director exposure = more survival.'
Specific effects will occur during a nuclear blast that starts a millisecond after impact and carries on for days.
An intense flash of light will appear within a millisecond of the explosion, and the initial radiation will be released.
At the same time, the surrounding ground will become a source of residual radiation and the electromagnetic pulse could knock out technologies and cause power outages.
And this is when the fireball will reach its largest size.
'Immediately, there are burn, eye and electromagnetic pulse risks,' Bakri shared.
Seconds after impact, fires will spark just miles away, and blast waves will reach at least one mile from the detonation site.
A fallout cloud will emerge minutes following the explosion like a massive mushroom-shaped cloud rising from the ground and then drop fallout particles back to Earth.
Within hours of the bomb dropping, the hazardous particles will be picked up by the wind and travel miles outside the impact zone.
In days following the explosion, low levels of fallout will make their way across the globe, creating patchy weather patterns.
Take cover with the proper shields
'The more 'stuff' between you and the blast, the better,' Bakri shared.
The medical physician explained that being indoors, underground, wearing more clothes and seeking shelter in structures made of lead will increase your survival.
''Radiation from a fallout is encountered in the forms of alpha, beta, and gamma radiation.' Ordinary clothing affords protection from alpha and beta radiation,' shared Bakri.
'Lead shelter is ideal as more thickness is better, Especially in the first 24 hours.'
He also explained that immediately after the blast, it is wise to remove contaminated clothes, shower or wash your body vigorously and avoid eating and inhaling radioactive material.
Bakri suggested that if a single piece of lead is available, the person should use it to shield their pelvis.
'The idea is to use enough shielding material to sufficiently protect the high concentration of bone marrow in the pelvic region, which contains enough regenerative stem cells to repopulate the body with unaffected bone marrow,' he posted. | Chemistry and Material Sciences |
The world’s largest source of natural diamonds — and of more than 90 percent of all natural pink diamonds found so far — may have formed due to the breakup of Earth’s first supercontinent, researchers report September 19 in Nature Communications.
The diamond-bearing rocks of the Argyle mine in Western Australia probably formed about 1.3 billion years ago, the analysis shows, along a rift zone that sundered the supercontinent Nuna. The finding suggests that exploring ancient rift zones for diamond troves may be more worthwhile than previously thought.
On Earth’s surface, carbon atoms tend to form soft, dull graphite. But down in the forge that is the upper mantle, extreme conditions mold the element into hard, dense gemstones (SN: 9/14/20). These diamonds can escape their chthonic womb by hitching a ride in rapidly ascending magmas (SN: 1/18/12). Near the surface, the molten material solidifies as vertical tubes of volcanic rock, known as kimberlite pipes. Most diamonds are found in these formations.
But this classic story does not explain the Argyle formation, nor its pink diamonds. To make a diamond blush, something more powerful than mere mantle conditions must contort its sturdy crystal structure, altering how it absorbs and transmits light.
Another wrinkle lies in Argyle’s diamondiferous pipes. They are not kimberlite, but rather lamproite pipes, which are generally thought to form at shallower depths, says geologist Maya Kopylova of the University of British Columbia in Vancouver, who was not involved in the new study.
Lamproites’ shallow origins may explain why they usually lack kimberlites’ rich diamond loads. The exception is Argyle — somehow, its lamproites raised treasures from the deep.
The oddities of the Argyle formation have long puzzled geologists. Chemical analyses conducted in the 1980s suggested it formed roughly 1.2 billion years ago. But that dating was questionable; the mineral that was analyzed may have been chemically altered by fluids in the Earth, potentially yielding a too-young age. What’s more, the results did little to clear up Argyle’s mysterious origins, says Hugo Olierook of Curtin University in Perth, Australia. “Nothing was really happening [geologically] in Australia at the time.”
So Olierook and colleagues dated resilient grains of the minerals apatite and zircon that fell into the lamproite when it was still molten. The researchers also analyzed titanite, a mineral that appears to have crystallized slightly later than the rest of the lamproite.
By measuring the quantities of radioactive elements and their decay products within each mineral, the team found that the lamproite formed about 1.3 billion years ago, roughly 100 million years earlier than previously suggested.
“When I first got the age, I thought, this doesn’t make any sense at all,” Olierook says. But while he was cycling home a couple of hours later, it clicked. “That’s when the first supercontinent was breaking up,” he says.
Argyle sits within an ancient continental suture, where two plates once collided to form part of Nuna, roughly 1.8 billion years ago (SN: 1/11/17). “It’s the smashing of those continents together; that’s what made those diamonds pink,” Olierook speculates.
Subscribe to Science News
Get great science journalism, from the most trusted source, delivered to your doorstep.
About 500 million years later, when Nuna rifted apart, that suture split like a reopened wound. That may have opened conduits for lamproite magmas laden with rosy gems to rise through, Olierook says.
For decades, it has been thought that tectonic processes like rifting destroyed diamonds, Kopylova says. But this research supports a recent paradigm shift, she says. Rifting “might be a trigger to get diamonds from deep in the mantle to the surface.”
Nonetheless, she says, it remains a mystery why Argyle’s lamproite pipes are the only ones known that contained minable quantities of diamonds. In late 2020, the diamond mine there stopped production after exhausting the diamonds that were economically feasible to extract.
It may be the case that more gem-studded lamproites are awaiting discovery, Olierook says. Perhaps somewhere, another Argyle lies hidden in the ruins of an ancient rift. | Chemistry and Material Sciences |
Data from the James Webb Space Telescope (JWST) has shown that an exoplanet around a star in the constellation Leo has some of the chemical markers that, on Earth, are associated with living organisms. But these are vague indications. So how likely is it that this exoplanet harbours alien life?
Exoplanets are worlds that orbit stars other than the Sun. The planet in question is named K2-18b. It’s so named because it was the first planet found to orbit the red dwarf star K2-18. There is a K2-18c as well – the second planet to be discovered. The star itself is dimmer and cooler than the Sun, meaning that, to get the same level of light as we do on Earth, the planet would need to be much closer to its star than we are.
The system is roughly 124 light years away, which is close in astronomical terms. So what are conditions like on this exoplanet? This is a difficult question to answer. We have telescopes and techniques powerful enough to tell us what the star is like, and how far away the exoplanet is, but we can’t capture direct images of the planet. We can work out a few basics, however.
Working out how much light hits K2-18b is important for assessing the planet’s potential for life. K2-18b orbits closer to its star than Earth does: it’s at roughly 16% of the distance from Earth to the Sun. Another measurement we need is the star’s power output: the total amount of energy it radiates per second. K2-18’s power output is 2.3% that of the Sun.
Using geometry, we can work out that K2-18b receives about 1.22 kilowatts (kW) in solar power per square metre. This is similar to the 1.36 kW of incoming light we receive on Earth. Although there’s less energy coming from K2-18, it evens out because the planet is closer. So far, so good. However, the incoming light calculation doesn’t take into account clouds or how reflective the planet’s surface is.
When we consider life on other planets, a popular term to use is the habitable zone, which means that at an average surface temperature, water will be in a liquid state – as this condition is considered essential for life. In 2019, the Hubble Space Telescope determined that K2-18b showed signs of water vapour, suggesting that liquid water would be present on the surface. It is currently thought that there are large oceans on the planet.
This caused a ripple of excitement at the time, but without further evidence it was just an interesting result. Now we have reports that JWST has identified carbon dioxide, methane and – possibly – the compound dimethyl sulfide (DMS) in the atmosphere. The tentative detection of DMS is significant because it is only produced on Earth by algae. We currently know of no way it can be naturally produced without a life-form.
Is there life on K2-18b?
All these indications seem to suggest that K2-18b might be the place to go to find alien life. It is not quite as simple as that, though, as we have no idea how accurate the results are. The method used to determine what is in the atmosphere of an exoplanet involves light from a different source (usually a star or galaxy) passing through the edge of the atmosphere that is then observed by us. Any chemical compounds will absorb light in specific wavelengths which can then be identified.
Imagine it as looking at a light bulb through a glass tumbler. You can see through it perfectly when empty. If you fill it with water, you can still see through pretty well, but there are some optical effects and colouration, which are the equivalent of hydrogen and dust clouds in space. Now imagine you poured in red food dye – this might be the equivalent of the main chemical constituent in a planet’s atmosphere.
But most atmospheres are made up of many chemicals. The equivalent of looking for any one of them would be like pouring 50 – likely many more – coloured food dyes, in different amounts, into your tumbler and trying to identify how much of one particular colour is present. It is an incredibly difficult task with plenty of room for subjective assessment and errors. In addition, the light going through the atmosphere contains a signal of the star’s chemical constituents – further complicating the analysis.
Only a few years ago there was a surge of interest in whether life existed on Venus, as observations had indicated the presence of phosphine gas, which can be produced by microbes.
However, this finding was later successfully refuted by several studies. If there can be confusion about what is in the atmosphere of a planet that’s just next door, in astronomical terms, it’s easy to see why analysing a planet that’s many times further away is a difficult task.
What can we take from this?
The chances of life on exoplanet K2-18b are low but not impossible. These results will likely not change anybody’s opinions or beliefs about extraterrestrial life. Instead, they do demonstrate the advancing ability to look into worlds that are not our own and find more information.
The power of JWST is not only in producing incredible pictures, but in providing more detailed and accurate data on celestial objects themselves. Knowing which exoplanets host water and which do not could provide information on how the Earth formed.
Studying the atmospheres of gas giant exoplanets can inform the study of similar worlds in the Solar System, such as Jupiter and Saturn. And identifying levels of CO2 indicates how an extreme greenhouse effect might affect a planet. This is the real power of studying the composition of planetary atmospheres.
The views expressed are those of the author and do not necessarily reflect the views of the publisher. | Chemistry and Material Sciences |
Scientists have observed the creation of rare chemical elements in the second-brightest gamma-ray burst ever seen -- casting new light on how heavy elements are made.
Researchersexamined the exceptionally bright gamma-ray burst GRB 230307A, which was caused by a neutron star merger. The explosion was observed using an array of ground and space-based telescopes, including NASA's James Webb Space Telescope, Fermi Gamma-ray Space Telescope, and Neil Gehrels Swift Observatory.
Publishing their findings today in Nature(25 Oct), the international research team which included experts from the University of Birmingham, reveal that they found the heavy chemical element tellurium, in the aftermath of the explosion.
Other elements such as iodine and thorium, which are needed to sustain life on earth, are also likely to be amongst the material ejected by the explosion, also known as a kilonova.
Dr Ben Gompertz, Assistant Professor of Astronomy at the University of Birmingham, and co-author of the study explains: "Gamma-ray bursts come from powerful jets travelling at almost the speed of light -- in this case driven by a collision between two neutron stars. These stars spent several billion years spiralling towards one another before colliding to produce the gamma-ray burst we observed in March this year. The merger site is the approximate length of the Milky Way (about 120,000 light-years) outside of their home galaxy, meaning they must have been launched out together.
"Colliding neutron stars provide the conditions needed to synthesise very heavy elements, and the radioactive glow of these new elements powered the kilonova we detected as the blast faded. Kilonovae are extremely rare and very difficult to observe and study, which is why this discovery is so exciting."
GRB 230307A was one of the brightest gamma-ray bursts ever observed -- over a million times brighter than the entire Milky Way Galaxy combined. This is the second time individual heavy elements have been detected using spectroscopic observations after a neutron star merger, providing invaluable insight into how these vital building blocks needed for life are formed.
Lead author of the study Andrew Levan, Professor of Astrophysics at Radboud University in the Netherlands, said: "Just over 150 years since Dmitri Mendeleev wrote down the periodic table of elements, we are now finally in the position to start filling in those last blanks of understanding where everything was made, thanks to the James Webb Telescope."
GRB 230307A lasted for 200 seconds, meaning it is categorised as a long-duration gamma-ray burst. This is unusual as short gamma-ray bursts, which last less than two seconds, are more commonly caused by neutron star mergers. Long gamma-ray bursts like this one are usually caused by the explosive death of a massive star.
The researchers are now seeking to learn more about how these neutron star mergers work and how they power these huge element-generating explosions.
Dr Samantha Oates, a co-author of the study while a postdoctoral research fellow at the University of Birmingham (now a lecturer at Lancaster University) said: "Just a few short years ago discoveries like this one would not have been possible, but thanks to the James Webb Space Telescope we can observe these mergers in exquisite detail."
Dr Gompertz concludes: "Until recently, we didn't think mergers could power gamma-ray bursts for more than two seconds. Our next job is to find more of these long-lived mergers and develop a better understanding of what drives them -- and whether even heavier elements are being created. This discovery has opened the door to a transformative understanding of our universe and how it works."
Story Source:
Journal Reference:
Cite This Page: | Chemistry and Material Sciences |
Saturday Citations: Hope for golden retrievers and humans. Plus: Cosmologists constrain the entire universe
This week, we reported on the totality of the universe. We reported on some other subjects, as well, but since they're obviously encompassed by that first thing, enough said.
Object occluded
People across the western U.S. last Saturday reported that one thing temporarily blocked another thing from view. The larger and more distant thing, normally visible in the sky, was briefly obscured by the smaller and closer thing. To better understand this phenomenon, hold an object in your hand at arm's length at an angle that obscures a more distant object across the room.
Totality comprehended
Researchers at The Australian National University produced what they call the most comprehensive view of the universe ever created. Their Zillow floor plan of all reality is a fairly simple chart depicting two plots: The first shows the temperature and density of the universe as it expanded and cooled; the second shows the possible mass and size of all objects in the universe.
The chart includes no-go zones, one where general relativity prohibits objects from becoming denser than black holes. Another is a zone in which matter enters a fuzzy state of quantum uncertainty and objects can't be defined. So basically, it's just a set of constraints. But I can see how placing constraints on the entire universe might make a cosmologist feel pretty big and strut around like a big shot.
The paper discusses Planck-mass instantons, the smallest mass a black hole can have without entering the zone of quantum uncertainty. They write, "The Hawking temperature of an instanton is the Planck temperature. Thus, we have assumed that the initial conditions of the universe are that of an instanton. Instantons seem to be an essential ingredient for quantum cosmology, and their study is an active field of research that is beyond the scope of this paper."
Bludgeon immortalized
Five hundred millennia ago, human ancestors developed a tool now called an Acheulean handaxe for cutting meat, chopping wood and digging. Jagged, ovular stones, they are shaped first by hard hammerstones, which broke off large flakes from the rock core, followed by the removal of smaller flakes. Variants have been found worldwide, wherever Homo erectus hung out and bashed things.
Prior to the Enlightenment, people thought they were formed naturally, and the earliest textual references to them date to the 1500s. But researchers at Dartmouth and the University of Cambridge have identified one of these sweet babies in an oil painting from 1455.
"The Melun Diptych," painted by Jean Fouquet, comprises two panels: On the left are two guys, and on the right, the Virgin Mary and her child surrounded by angels. The handaxe is depicted in the left panel, resting on a New Testament in the arm of Saint Stephen, representing his death by stoning.
It had never been previously identified as an Acheulean handaxe, but in 2021, Steven Kangas, a senior lecturer in the Department of Art History at Dartmouth, had the opportunity to show two anthropologists an image of the left panel and they agreed that it resembled a handaxe, ultimately confirming it via three analyses.
Boy good
If you're ranking dog breeds, golden retrievers have to be in the top five in terms of sociability, temperament and utility—they'll help carry groceries in from the car and even prefer to hold their own leash on a walk. They just like carrying stuff. When he heard the doorbell ring, my sister's golden retriever Hudson would run to the door with a present for visitors, usually a dog toy covered in slobber.
Goldens may also contribute to a better understanding of human cancer. Unfortunately, for reasons not completely understood, golden retrievers have a 65% chance of dying from cancer. Now, researchers at the University of California, Davis, have published a study in which they looked for genes associated with longer life.
They found expression of gene HER4 in goldens with long lifespans; it is a member of a family of human epidermal growth factor receptors important in human cancer, and it may mitigate against the genetic predisposition to cancer in goldens. Co-author Robert Rebhun said, "If we find that this variant in HER4 is important either in the formation or progression of cancer in golden retrievers, or if it can actually modify a cancer risk in this cancer predisposed population, that may be something that can be used in future cancer studies in humans."
Shareholders awful
For the last 40-odd years, economists have been punching us in the throat with an ideology emphasizing the infallibility of the market in driving social progress. So it stands to reason that we should use market-based interventions to reduce oil and gas production, right?
Haha, checkmate, environmentalists, divestment from fossil fuel holdings by small investors is almost immediately canceled out by mega-shareholder buys, according to a new report from the Center for Climate Crime and Climate Justice at Queen Mary University of London.
Among its findings, 25% of the investors studied who made significant reductions in either BP or Shell increased their holdings in the other company. And it argues that the enormous increases in market capitalization and and share price for the two companies shows that divestment campaigns in general are not making their intended impact.
The report, titled "Beyond Divestment," argues that the ineffectiveness of divestment of BP and Shell shares should motivate governments to pursue other interventions that actually scale back production.
© 2023 Science X Network | Chemistry and Material Sciences |
This article has been reviewed according to Science X's
editorial process
and policies.
Editors have highlighted
the following attributes while ensuring the content's credibility:
fact-checked
peer-reviewed publication
reputable news agency
proofread
Hidden ocean the source of carbon dioxide on Jupiter moon: Research
by Daniel Lawler
Carbon dioxide detected on Jupiter's moon Europa comes from the vast ocean beneath its icy shell, research using James Webb Space Telescope data indicated on Thursday, potentially bolstering hopes the hidden water could harbor life.
Scientists are confident there is a huge ocean of saltwater kilometers below Europa's ice-covered surface, making the moon a prime candidate for hosting extra-terrestrial life in our Solar System.
But determining whether this concealed ocean has the right chemical elements to support life has been difficult.
Carbon dioxide—one of the key building blocks of life—has been detected on Europa's surface, but whether it rose up from the ocean below remained an open question.
Aiming to find an answer, two US-led teams of researchers used data from the Webb telescope's near-infrared spectrometer to map CO2 on the surface of Europa, publishing their results in separate studies in the journal Science.
The most CO2 was in a 1,800 kilometer-wide (1,120 mile) area called Tara Regio, where there is a lot of "chaos terrain" with jagged ridges and cracks.
Exactly what creates chaos terrain is not well understood, but one theory is that warm water from the ocean rises up to melt the surface ice, which then re-freezes over time into new uneven crags.
The first study used the Webb data to look at whether the CO2 could have come from somewhere other than the ocean below—hitching a ride on a meteorite, for example.
Samantha Trumbo, a planetary scientist at Cornell University and the study's lead author, told AFP they concluded that the carbon was "ultimately derived from the interior, likely the internal ocean".
But the researchers could not rule out that the carbon came up from the planet's interior as rock-like carbonate minerals, which irradiation could then have broken apart to become CO2.
'Very exciting'
Table salt has also been detected in Tara Regio—making the area significantly more yellow than the rest of Europa's scarred white plains—and scientists think it may also have come up from the ocean.
"So now we've got salt, we've got CO2: we're starting to learn a little bit more what that internal chemistry might look like," Trumbo said.
Looking at the same Webb data, the second study also indicated that "carbon is sourced from within Europa".
The NASA-led researchers had also hoped to find plumes of water or volatile gases shooting out of the moon's surface, but failed to spot any.
Two major space missions plan to get a closer look at Europa and its mysterious ocean.
The European Space Agency's Jupiter moon probe Juice launched in April, while NASA's Europa Clipper mission is scheduled to blast off in October 2024.
Juice project scientist Olivier Witasse welcomed the two new studies, saying they were "very exciting".
When Juice flies past Europa twice in 2032, it will collect "a wealth of new information," including about surface chemistry, he told AFP.
Juice will also look at two of Jupiter's other moons—Ganymede and Callisto—where carbon has been detected.
Witasse emphasized that the goal of the Juice mission, like the Europa Clipper, is to find out whether these icy moons have the right conditions to support life—they will not be able to confirm if aliens exist.
And even if some future mission does discover life, anything able to live in such extreme conditions under more than 10 kilometers of ice is expected to be tiny, such as primitive microbes.
Citation:
Hidden ocean the source of carbon dioxide on Jupiter moon: Research (2023, September 21)
retrieved 21 September 2023
from https://phys.org/news/2023-09-hidden-ocean-source-carbon-dioxide.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.
This site uses cookies to assist with navigation, analyse your use of our services, collect data for ads personalisation and provide content from third parties.
By using our site, you acknowledge that you have read and understand our Privacy Policy
and Terms of Use. | Chemistry and Material Sciences |
The Indian Space Research Organisation’s (ISRO) Moon lander Vikram and robotic rover Pragyan have now been told to go to sleep. ISRO hopes to awaken them at lunar dawn on 22 September.
But in their two-week sojourn around the Moon’s south pole, they provided insights that have planetary scientists abuzz. Here are some of the first remarkable findings.
A thin soup of ions and electrons swirls near the lunar pole
A probe onboard Vikram made the first measurements of the density and temperature of Moon’s ionosphere. ISRO reports a “relatively sparse” mix of ions and electrons in the 100-kilometre-thick layer of electrically charged plasma that surrounds the Moon’s surface near the south pole.
Initial measurements of the plasma indicate a density of about 5 million to 30 million electrons per cubic metre. And the density seems to vary as the lunar day progresses, an ISRO scientist analysing the Chandrayaan-3 mission's data told Nature. The peak density of a similar layer in Earth’s upper atmosphere is one million electrons per cubic centimetre.
The density of the ionosphere would affect lunar communication and navigation systems if humans were to inhabit the Moon — the higher the electron density, the longer radio signals take to travel through the ionosphere. The sparse plasma means that potential delays would be “minimal”, the scientist says, and would not pose a problem for transmission.
Temperature variations with depth
Understanding lunar soil, including its temperature and conductivity, will be important when considering settlement on the Moon. The soil “is an important in situ resource for construction”, says Anil Bhardwaj, director of ISRO’s Physical Research Laboratory in Ahmedabad.
The lander is fitted with a temperature probe containing 10 sensors and able to reach 10 centimetres below the surface of the Moon. Its preliminary data show that during the day, the temperature 8 cm down is around 60 ºC lower than at the surface.
Planetary scientist Paul Hayne at the University of Colorado Boulder, says that a steep decline in temperature is expected during the lunar daytime, because the heat does not conduct downward from the warm sunlit surface. “This is similar to the effect one experiences when visiting a beach on a hot day — dig down just a few centimetres and the sand is much cooler,” he says.
Measurements so far have found that the temperature at the surface is significantly warmer than recorded by NASA’s 2009 Lunar Reconnaissance Orbiter, adds Hayne.
The temperatures “are far too warm for water ice to be stable”, says Hayne, explaining that water converts from solid to gas at a very low temperature in the vacuum of space — at about −160 ºC. Chandrayaan-3’s data indicate temperatures warmer than −10 ºC at all depths sampled. Further down "we expect temperatures to flatten out at close to the average surface temperature of about −80 ºC,” says Hayne.
A suspected moonquake
Among many vibrations recorded by the lander’s seismograph, one in particular caught the attention of scientists. The instrument “seems to have recorded a very small seismic event that decayed to background in about 4 seconds”, says planetary geochemist Marc Norman at the Australian National University in Canberra. ISRO scientists suspect it was a small moonquake or the impact of a tiny meteorite.
Such perturbations are expected on the Moon. “Small impacts and local tectonic adjustments related to tidal forces are common on the Moon, but we really need a global seismic network on the Moon and longer-term observations to understand the significance of any particular event,” says Norman.
Sulfur confirmed
Testing by the rover unambiguously confirms the presence of sulfur in the lunar surface near the south pole, ISRO reports. It also found aluminium, silicon, calcium and iron, among other elements.
“Sulfur, being volatile, is not generally expected,” explains Bhardwaj. Confirmation of its presence is really important, say scientists. Sulfur is a key element of molten rock, and researchers think that the primitive Moon was covered with a thick layer of hot molten rock, which crystallized to form the Moon’s surface. Measurements of sulfur concentrations can provide insight into that process, says the ISRO scientist. However, it’s also possible that the sulfur came from asteroids that bombard the Moon’s surface. The ISRO scientist says they hope to add their findings to those of the US Apollo missions to better understand the Moon’s geochemistry. | Chemistry and Material Sciences |
NASA lab hopes to find life's building blocks in asteroid sample
Eager scientists and a gleaming lab awaits.
A sample from the asteroid Bennu, which could be key to understanding the formation of the solar system and our own planet, is set to be analyzed at NASA's Johnson Space Center in Houston after it reaches Earth in late September.
The precious cargo is currently aboard OSIRIS-REx, a US space probe launched in 2016 to Bennu, which orbits the Sun at an average distance of about 105 million miles (168 million kilometers).
Long white sleeves hang from the huge metal and glass box in which the sample will be handled.
Scientists will separate pieces of the rock and dust for study now, while carefully storing away the rest for future generations equipped with better technology—a practice first started during the Apollo missions to the Moon.
"We don't expect there to be anything living but (rather) the building blocks of life," Nicole Lunning, lead OSIRIS-Rex sample curator, told AFP.
"That's really what motivated going to this type of asteroid, to understand what the precursors were that may have fostered life in our solar system and on Earth."
Once the return vessel arrives at the Texas "cleanroom," Lunning's job will be to carefully disassemble it and separate the contents, all while keeping the material pure and uncontaminated.
Origins of life
The spacecraft is scheduled to land in the Utah desert on September 24, carrying an estimated 8.8 ounces, or 250 grams of material—just over a cupful.
Obtaining it involved a high-risk operation in October 2020: the probe came into contact with the asteroid for a few seconds, and a blast of compressed nitrogen was emitted to raise the dust sample which was then captured.
The whole mission was imperiled when NASA realized a few days later that the valve of the collection compartment was failing to close, letting fragments escape into space.
But the precious cargo was finally secured after being transferred to a capsule fixed in the spacecraft's center.
The first samples brought to Earth by asteroids were carried out by Japanese probes in 2010 and 2020, with the latter found to contain uracil, one of the building blocks of RNA.
The finding lent weight to a longstanding theory that life on Earth may have been seeded from outer space when asteroids crashed into our planet carrying fundamental elements.
Cosmochemist Eve Berger can't wait to get to work on the Bennu material.
"These samples haven't hit the Earth. They haven't been exposed to our atmosphere. They haven't been exposed to really anything except harsh space for billions of years," she said.
Ultimately they "will help us to determine whether what we really think is true, is true," said Berger.
Not only might the Bennu sample add to our knowledge of the ingredients that brought life to our world, but "if we can figure out what happened here on the Earth, that helps us to extrapolate to other bodies where we might look or how we might interpret what we're seeing," she added.
Could Bennu bring back something that's never been seen before? "You never know," said Berger.
"Bennu is a trickster, so we'll know more in a few months when the sample comes back—that would be exciting!"
© 2023 AFP | Chemistry and Material Sciences |
Kris Pardo is an Assistant Professor of Physics & Astronomy at the University of Southern California.
Most scientists care about the newest techniques, data and theories in their field, but they often know very little about the history of their discipline. Astronomers, like me, are no exception.
It wasn't until I taught an intro to astronomy class that I learned about Caroline. Now, thanks to a new display of her papers at the Herschel Museum in Bath, England, others will get to learn about her too. Her story reflects not only the priorities of astronomy but also how credit is assigned in the field.
Related: Caroline Herschel Biography
Her path to astronomy
Caroline Herschel, born in 1750, did not have an easy childhood. After a bout with typhus left her scarred at a young age, her family assumed that she would never marry and treated her as an unpaid servant. She was forced to complete household chores, despite showing a keen interest in learning from a young age. She eventually escaped her family to follow her older brother William Herschel, whom she adored, to Bath.
Caroline was a somewhat unwilling astronomer at first. She didn't become interested in astronomy until William was already thoroughly engrossed in the subject. Although she spoke somewhat disparagingly about how she followed her brother to different interests, including music and astronomy, Caroline eventually acknowledged her real interest in studying astronomical bodies.
Astronomers at the time were mainly interested in finding new objects and mapping out the heavens with precision. Using telescopes to look for new comets and nebulae was also popular. William Herschel became famous after his discovery of Uranus in 1781, though he mistook the planet for a comet at first.
At the beginning of her career, Caroline worked as William’s assistant. She focused mostly on astronomical instrumentation tasks, like polishing telescope mirrors. She also helped copy catalogs and took careful notes about William's observations. But then she began to make her own observations.
Searching the skies
In 1782, Caroline began recording the positions of new objects in her own logbook. It was through this work that she discovered several comets and nebulae. On Aug. 1, 1782, she discovered a comet – meaning she was the first to see it in a telescope with her own eyes. This was the first comet discovery attributed to a woman. She went on to discover seven more comets over the next 11 years.
At the time of the Herschels' work, it was the actual observation of an object that warranted public recognition, so Caroline was given credit only for the comets she saw through the telescope herself. For all of her other work, like recording and organizing all the data from William's observations, she received less credit than William.
For instance, when Caroline took all of William's observations and compiled them into a catalog, it was published under William's name. Caroline is mentioned only as an "assistant" in the paper.
Nonetheless, in recognition of her discoveries and her work as William's assistant, King George III of England granted Caroline a salary, making her the first professional female astronomer.
Later in life, Caroline reorganized the same catalog in a more efficient way, according to how practicing astronomers interested in looking for comets actually observed the night sky. This updated catalog was later used as the basis of the New General Catalogue, which astronomers still use today to organize the stars.
The Herschels also created the first – though not quite correct – map of our galaxy, the Milky Way.
Who gets the credit in astronomy?
Recognition for scientific work within the astronomical community is pretty different now than it was in the Herschels' day. In fact, most of the astronomers who receive credit today are those whose work looks a lot like Caroline's – recording and organizing data about astronomical observations.
Astronomers seldom put their eyeballs up to a telescope eyepiece anymore, and many of the most important discoveries are made by telescopes in space. But astronomers still need to be able to make sense of all the data from these telescopes. Catalogs like the ones Caroline made are important tools for doing so.
Most people today haven't heard of Caroline Herschel. Despite having several astronomical objects – and even a satellite – named after her, she doesn't have the same name recognition as the other astronomers of her time. Some of the lack of recognition is probably because her brother received all the credit for her catalog. Today, astronomers would give them both credit.
Herschel is just one in a long line of female astronomers who did not receive the credit they were due and whose work was used to justify prizes for male scientists instead. These issues aren’t just restricted to 18th-century science, but persist through modern astronomy as well. Jocelyn Bell Burnell, who discovered the first radio pulsar, was left off the 1974 Nobel Prize, and the award was instead granted to her Ph.D. adviser.
Although astronomy has come a long way since the 18th century, astronomers still need to think carefully about how to fairly recognize the people who participate in scientific discoveries. Acknowledging the contributions of astronomers like Caroline Herschel is a small step toward giving credit where credit is due.
Follow all of the Expert Voices issues and debates — and become part of the discussion — on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher. | Chemistry and Material Sciences |
Secrets of the Ice
toggle caption
An archeologist holds an arrow originally believed to be from the Iron Age on Mount Lauvhøe in Norway. Upon closer inspection, the team determined the artifact is from the Stone Age and is likely around 4,000 years old.
Secrets of the Ice
An archeologist holds an arrow originally believed to be from the Iron Age on Mount Lauvhøe in Norway. Upon closer inspection, the team determined the artifact is from the Stone Age and is likely around 4,000 years old.
Secrets of the Ice
Archeologists in Norway discovered an arrow shaft that appears to be from the Stone Age, meaning it is approximately 4,000 years old.
The discovery was made on the side of Mount Lauvhøe, which stands at just over 6,500 feet in Norway's Lom Municipality. Archeologists had found arrows from the Iron and Middle ages when they last surveyed the area in 2017. However, this arrow shaft was found after ice at the site melted away in recent years, according to Lars Holger Pilø, co-director Secrets of the Ice, part of Norway's Department of Cultural Heritage.
He said the discovery predates earlier finds by more than 2,000 years, which adds a lot more "time depth" to the site. Researchers can determine the age of the artifact by its shape, but will submit a sample of the wood for carbon dating once the field season is over.
The find is likely evidence of ancient hunters stalking reindeer, which made their way onto the snow and ice in summer months thousands of years ago to avoid clouds of botflies.
"Sometimes, when an arrow missed its target, it burrowed itself deep into the snow and was lost," Pilø posted. "Sad for the hunter but a bull's eye for archaeology!"
The area where the arrow shaft was found is one of 66 ice sites in Norway, which have preserved more than 4,000 archeological finds over the years, Pilø said.
Since the arrow shaft was broken at both ends, it was difficult to date, according to a Secrets of the Ice post on X, the social media platform formerly known as Twitter. Archeologists initially thought the artifact was from the Iron Age, but after removing glacial silt, experts determined it was far older than they initially thought.
"The arrowhead is likely to have been a pressure-flaked stone projectile, meaning that the arrow is probably around 4,000 years old," the post reads.
In another post, archeologists described how the preserving power of ice over time: "The ice is a time machine: It brings precious objects from the past to our time in an unaltered state, like sleeping beauties." | Chemistry and Material Sciences |
Introduction
Our planet is doomed. In a few billion years, the sun will exhaust its hydrogen fuel and swell into a red giant — a star so big it will scorch, blacken and swallow up the inner planets.
While red giants are bad news for planets, they’re good news for astrophysicists. Their hearts hold the keys to understanding a range of stellar bodies, from fledgling protostars to zombie white dwarfs, because deep within them lies an invisible force that can shape a star’s destiny: the magnetic field.
Magnetic fields near the surfaces of stars are often well characterized, but what’s happening in their cores is mostly unknown. That’s changing, because red giants are uniquely suited for studying magnetism deep within a star. Scientists do this by using starquakes — subtle oscillations at a star’s surface — as a portal to stellar interiors.
“Red giants have these oscillations that allow you to probe the core very sensitively,” said Tim Bedding, an asteroseismologist at the University of Sydney who studies red giant stars.
Last year, a team at the University of Toulouse decoded those oscillations and measured the magnetic fields within a trio of red giants. Earlier this year, the same team detected magnetic fields inside a further 11 red giants. Together, the observations showed that the hearts of giants are more mysterious than expected.
Close to a star’s heart, magnetic fields play crucial roles in chemical mixing in the star’s interior, which in turn affects how a star evolves. By refining stellar models and including internal magnetism, scientists will be able to calculate stellar ages more accurately. Such measurements could help determine the ages of potentially habitable faraway planets and pin down the timelines of galaxy formation.
“We don’t include magnetism in stellar modeling,” said Lisa Bugnet, an astrophysicist at the Institute of Science and Technology Austria who developed methods for studying magnetic fields inside red giants. “It’s crazy, but it’s just not there because we have no idea how it looks [or] how strong it is.”
Stare Into the Sun
The only way to probe the heart of a star is with asteroseismology, the study of stellar oscillations.
In the same way that seismic waves rippling through Earth’s interior can be used to map the planet’s subterranean landscape, stellar oscillations open a window into a star’s innards. Stars oscillate as their plasma churns, producing waves that carry information about a star’s internal composition and rotation. Bugnet compares the process to a ringing bell — the shape and size of a bell produces a specific sound that reveals the properties of the bell itself.
To study quaking giants, scientists use data from NASA’s planet-hunting Kepler telescope, which monitored the brightness of over 180,000 stars for years. Its sensitivity allowed astrophysicists to detect minute changes in starlight linked to stellar oscillations, which affect both the radius and the brightness of the star.
But decoding stellar oscillations is tricky. They come in two basic flavors: acoustic pressure modes (p-modes), which are sound waves that move through the outer regions of a star, and gravity modes (g-modes), which are lower in frequency and mostly confined to the core. For stars like our sun, p-modes dominate their observable oscillations; their g-modes, which are affected by internal magnetic fields, are too weak to detect and can’t reach the star’s surface.
In 2011, the KU Leuven astrophysicist Paul Beck and colleagues used Kepler data to show that in red giants, p-modes and g-modes interact and produce what’s known as a mixed mode. The mixed modes are the tool that probes the heart of a star — they allow astronomers to see the g-mode oscillations — and they’re only detectable in red giant stars. Studying mixed modes revealed that red giant cores rotate much more slowly than the star’s gaseous envelope, contrary to what astrophysicists had predicted.
That was a surprise — and a possible indication that something crucial was missing in those models: magnetism.
Stellar Symmetry
Last year, Gang Li, an asteroseismologist now at KU Leuven, went digging through Kepler’s giants. He was searching for a mixed-mode signal that recorded the magnetic field in the core of a red giant. “Astonishingly, I actually found a few instances of this phenomenon,” he said.
Typically, mixed-mode oscillations in red giants occur almost rhythmically, producing a symmetric signal. Bugnet and others had predicted that magnetic fields would break that symmetry, but no one was able to make that tricky observation — until Li’s team.
Li and his colleagues found a giant trio that exhibited the predicted asymmetries, and they calculated that each star’s magnetic field was up to “2,000 times the strength of a typical fridge magnet” — strong, but consistent with predictions.
However, one of the three red giants surprised them: Its mixed-mode signal was backward. “We were a bit puzzled,” said Sébastien Deheuvels, a study author and an astrophysicist at Toulouse. Deheuvels thinks this result suggests that the star’s magnetic field is tipped on its side, meaning that the technique could determine the orientation of magnetic fields, which is crucial for updating models of stellar evolution.
A second study, led by Deheuvels, used mixed-mode asteroseismology to detect magnetic fields in the cores of 11 red giants. Here, the team explored how those fields affected the properties of g-modes — which, Deheuvels noted, may provide a way to move beyond red giants and detect magnetic fields in stars that don’t show those rare asymmetries. But first “we want to find the number of red giants that show this behavior and compare them to different scenarios for the formation of these magnetic fields,” Deheuvels said.
Not Just a Number
Using starquakes to investigate the interiors of stars kicked off a “renaissance” in stellar evolution, said Conny Aerts, an astrophysicist at KU Leuven.
The renaissance has far-reaching implications for our understanding of stars and of our place in the cosmos. So far, we know the exact age of just one star — our sun — which scientists determined based on the chemical composition of meteorites that formed during the birth of the solar system. For every other star in the universe, we only have estimated ages based on rotation and mass. Add internal magnetism, and you have a way to estimate stellar ages with more precision.
And age is not just a number, but a tool that could help answer some of the most profound questions about the cosmos. Take the search for extraterrestrial life. Since 1992, scientists have spotted more than 5,400 exoplanets. The next step is to characterize those worlds and determine if they’re suitable for life. That includes knowing the planet’s age. “And the only way you can know its age is by knowing the age of the host star,” Deheuvels said.
Another field that requires precise stellar ages is galactic archaeology, the study of how galaxies are assembled. The Milky Way, for instance, gobbled up smaller galaxies during its evolution; astrophysicists know this because chemical abundances in stars trace their ancestry. But they don’t have a good timeline for when that happened — the inferred stellar ages aren’t accurate enough.
“The reality is, sometimes we are a factor [of] 10 wrong in stellar age,” Aerts said.
The study of magnetic fields within stellar hearts is still in its infancy; there are many unknowns when it comes to understanding how stars evolve. And for Aerts, there’s beauty in that.
“Nature is more imaginative than we are,” she said.
Jackson Ryan’s travel for this story was partly funded by the ISTA Science Journalist in Residence Program. | Chemistry and Material Sciences |
Venus' youthful appearance could be the result of a ferocious bombardment by asteroids and comets, whose high-energy impacts superheated the planet's interior, a new study reports.
Planetary scientists estimate the age of a planet's surface by counting the number of craters embedded in it. The more craters there are, the older that surface must be to have allowed time for all those impacts to take place.
Earth has very few visible impact craters, and its surface is constantly churned over by subduction zones at the boundaries between continental plates.
Venus, too, has relatively few craters, and a surface estimated to be less than a billion years old. Yet Venus does not have plate tectonics, so it cannot renew its surface in the same way that Earth does over geological time periods.
What Venus does have is volcanoes, and a lot of them — more than 80,000, in fact. Most of these are volcanic vents from which lava seeps out rather than explosive volcanoes from mountaintop calderas, and earlier this year scientists made the first discovery of active volcanism on the Venusian surface. Over geological timescales, lava can flood the planet's surface, filling in craters and creating a more youthful appearance than Venus' true age of 4.5 billion years.
On Earth, plate tectonics are the main driver of volcanism, but since Venus lacks plate tectonics, what drives its volcanic activity has been something of a mystery. One leading theory had been that Venus endures bouts of cataclysmic volcanism every 500 million years or so as heat builds up beneath a thick, stagnant crust, but the mechanism to allow this had always been vaguely described. And so a team of planetary scientists, led by Simone Marchi of the Southwest Research Institute (SwRI) in San Antonio, Texas, have found another possible explanation.
Early in the history of the solar system, the inner planets were being pelted by asteroids and comets. Marchi's team compared the impact histories of Earth and Venus, and found that Venus was hammered by more energetic impacts.
"Higher-impact velocities melt more silicate, melting as much as 82% of Venus' mantle," said study co-author Raluca Rufu of SwRI in a statement.
This extra energy superheated Venus' interior, supporting billions of years' worth of volcanism, the new research found.
"Our latest models show that long-lived volcanism driven by early, energetic collisions on Venus offer a compelling explanation for its young surface age," said Jun Korenaga, a co-author from Yale University.
For now, this remains only a compelling hypothesis, but forthcoming missions to Venus may be able to find evidence to support it. These include the European Space Agency's EnVision mission that will launch in the early 2030s, and NASA's VERITAS (Venus Emissivity, Radio Science, InSAR, Topography and Spectroscopy) orbiter.
Both missions will study Venus' surface and geological activity in its subsurface. However, NASA has postponed the VERITAS mission due to budget squeezes, although a second mission called DAVINCI (Deep Atmosphere Venus Investigation of Noble gases, Chemistry and Imaging), is still going ahead as planned, targeting a 2029 launch to study the planet's dense atmosphere. DAVINCI also might be able to confirm or rule out the existence of phosphine, a potential biosignature that has been the subject of recent controversial claims.
"Interest in Venus is high right now," said Marchi. "These findings will have synergy with the upcoming missions, and the mission data could help confirm the findings."
The research was published last week in the journal Nature Astronomy. | Chemistry and Material Sciences |
The Osiris-Rex spacecraft successfully picked up the materials from an asteroid called Bennu in October 2020, 205 million miles from Earth. It then took almost three years for the NASA probe to come home and drop off its precious cargo in a Utah desert. That happened on 24 September. Now, what the probe contained is being revealed.
As it's less than a month since NASA got its hands on this 'first of its kind' cargo, there are - as yet - no earth shattering results. However, the good news is that the black, extraterrestrial powder has already proved to be rich in carbon and water-laden minerals.
It's a good sign that the samples taken from the 500m wide asteroid will be able to reveal new information about the formation of the Solar System, billions of years ago.
Bennu interests scientists because it likely retains the chemistry that existed when the planets began forming around the nascent Sun. There's a theory that carbon-rich (organic), water-rich asteroids similar to Bennu may have been involved in delivering key components to the Earth system, such as the water in our oceans and some of the compounds that had a role in kick-starting life.
The researchers, when they examine the returned samples in detail, will be looking for indications that might support or counter these ideas.
"We're going to get a lot of new information from Bennu to really understand exactly just how complex are these organic molecules that we find," explained Dr Lori Glaze, the director of planetary science at NASA.
"The samples will feed our understanding of how the earliest organic building blocks might have come together to form life on Earth and perhaps elsewhere in the Solar System, too. I think that's going to be incredibly valuable," she told BBC News. | Chemistry and Material Sciences |
NASA is preparing to launch its Psyche spacecraft on the first mission designed to study a metal-rich asteroid up close. The Psyche mission is set to blast off on Thursday (Oct. 12) from NASA's Kennedy Space Center in Florida at 10:16 a.m. EDT (1416 GMT) atop a SpaceX Falcon Heavy rocket.
After traveling an estimated 2.2 billion miles (3.5 billion kilometers), the spacecraft will arrive at the asteroid 16 Psyche, which is located at the far edge of the main asteroid belt between Mars and Jupiter, in 2029.
Once the spacecraft is in place, mission scientists will study the metal asteroid, which is different from the rock- and ice-dominated bodies studied in situ in the past, to learn more about how the rocky planets of the solar system (Mercury, Venus, Earth and Mars) formed.
What's so special about metal asteroid Psyche?
Discovered in 1852, Psyche is considered one of the most fascinating objects in the main asteroid belt, and scientists have only been able to study it at a distance. Scientists think the asteroid is composed of the exposed core of a planetesimal, a small body that formed during planet formation as gas and dust around a star collapsed in dense patches.
A planetesimal could eventually go on to gather more mass and thus become a planet. But Psyche is thought to have failed to reach planet status because it collided with other larger bodies as the solar system was forming around 4.5 billion years ago, possibly stripping the metal-rich asteroid of its outer rocky shell and exposing its iron-rich core.
That means that studying this 173-mile-wide (279 km), potato-shaped asteroid could not only help reveal more about the collisions that took place in the early solar system but also provide scientists with a proxy for the inaccessible iron core of our own planet.
Psyche seems to diverge from the solar system planets born from planetesimals. Whereas the rocks of the inner solar system planets are replete with iron oxides — chemical compounds of iron and oxygen atoms — Psyche lacks these compounds. If Psyche is indeed composed of material left over from the birth of the rocky planets, its existence could point to a different type of planetary formation that diverges from the mechanism that created Earth.
But even if Psyche turns out not to be an exposed planetesimal core, the asteroid is still very interesting to scientists because it could mean it belongs toa population of never-before-seen primordial solar system bodies.
What's so special about NASA's Psyche mission?
One of the most vital parts of the Psyche mission will be getting the spacecraft to this distant asteroid and then keeping it in place so its scientific instruments can do their jobs.
To do this, the spacecraft, which measures 16.1 by 7.1 by 7.8 feet (4.9 by 2.2 by 2.4 meters), will depend on a solar electric propulsion system that captures sunlight with its large solar arrays and then converts it to electric and magnetic fields. These fields accelerate charged atoms of the propellant xenon , which is commonly found in plasma televisions on Earth. These atoms, in the form of blue-glowing ionized gas, are then blasted out into space by the Psyche spacecraft's four thrusters, providing the craft with propulsion that looks like something straight out of science fiction.
According to NASA, each of these four thrusters operates one at a time, providing a force equivalent to the weight of three quarters in your hand here on Earth — which, in the microgravity and frictionless environment of space, is enough to propel the spacecraft.
Even with these revolutionary "Hall-effect thrusters" — which, so far, have been used to get only as far as the moon — the spacecraft's journey to the vicinity of Jupiter won't be a 'straight shot." Instead, it will require a gravity-assisted slingshot maneuver around Mars in 2026, and Psyche will arrive at its metal-rich asteroid target in August 2029.
The spacecraft will then make orbits of the asteroid at a distance of around 430 miles (700 km), which will decrease as the mission proceeds. The spacecraft will use progressively closer orbital periods , or "regimes ," to investigate different characteristics of the asteroid.
During its first orbital regime (A), lasting 56 days, the spacecraft will use its magnetometer to search Psyche for an ancient magnetic field, which would provide evidence that the asteroid was once a planetary body. As the spacecraft does this, its multispectral imager will assess the topography of Psyche's surface. This will continue as the NASA orbiter draws closer to the asteroid, hopefully revealing more details of these characteristics, particularly during the next two orbital regimes (B1 and B2), which will last 192 days.
Moving even closer to the asteroid, during the 100-day orbital regime C, Psyche's telecommunications system, which sends data to Earth and receives commands from ground control via radio waves, will be used to investigate the gravitational influence of the metal-rich asteroid. This could help better constrain its mass and density and thus the asteroid's interior composition and structure.
During its 100-day orbital regime D, Psyche will employ its gamma-ray neutron spectrometer to get a better picture of the asteroid's surface topology and investigate the chemical elements that are abundant on the asteroid's surface.
The Psyche mission is the result of a collaboration among several institutions, including Arizona State University, which provided the spacecraft's multispectral imager; NASA's Jet Propulsion Laboratory, which is responsible for mission management, operations and navigation; Maxar Technologies, which provided the chassis for the solar electric propulsion system and other hardware; and NASA's Launch Services Program at Kennedy Space Center, which acquired the SpaceX Falcon Heavy rocket for launch and will handle launch services.
You can watch the launch Thursday beginning at 9:30 a.m. EDT (1330 GMT) on NASA TV and directly on Space.com courtesy of NASA. | Chemistry and Material Sciences |
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more.
A pristine asteroid sample that could serve as a time capsule from the early days of our solar system has finally been revealed.
The rocks and dust contain water and a large amount of carbon, said NASA administrator Bill Nelson, which suggests that asteroids like Bennu may have delivered the building blocks of life to Earth. The sample is nearly 5% carbon by weight.
“The first analysis shows samples that contain abundant water in the form of hydrated clay minerals, and they contain carbon as both minerals and organic molecules,” Nelson said. “Far exceeding our goal of 60 grams, this is the biggest carbon-rich asteroid sample ever return to Earth. The carbon and water molecules are exactly the kinds of material that we wanted to find. They’re crucial elements in the formation of our own planet. And they’re going to help us determine the origin of elements that could have led to life.”
The sample collected from the 4.5 billion-year-old near-Earth asteroid Bennu in October 2020 by NASA’s OSIRIS-REx mission arrived on Earth in a capsule on September 24, dropping from the spacecraft and landing in the Utah desert.
Since then, scientists have been hard at work studying the wealth of material — more than they expected — just inside the top of the canister to conduct an early analysis. The results of that analysis, and the first look at the sample, were shared during a live NASA broadcast from the agency’s Johnson Space Center in Houston on Wednesday. It’s the largest asteroid sample returned to Earth.
When the OSIRIS-REx spacecraft closely approached Bennu three years ago, it extended a Touch-and-Go Sample Acquisition Mechanism head, or TAGSAM, toward the asteroid and fired a blast of nitrogen gas. The burst of gas lifted rocks and dust all the way from 19 inches (50 centimeters) beneath the space rock’s surface. That debris flowed into the TAGSAM head.
The TAGSAM also had 24 surface contact pads that touched the asteroid and trapped fine-grained material.
Together, the dust and rocks collected from Bennu’s surface and its interior could reveal the history of how the asteroid formed and evolved over time. These insights will also shed light on the space rock’s overall composition, which could help NASA determine how it might deflect the asteroid, which has a chance of impacting Earth in the future.
The much-anticipated reveal has been seven years in the making, from the OSIRIS-REx mission’s launch in 2016 to the capsule landing last month. Some have looked forward to the moment for even longer. OSIRIS-REx principal investigator Dante Lauretta, who helped develop the mission during its earliest stages, has waited nearly 20 years to see the sample and glean the insights it might reveal about our solar system.
Scientists will analyze the rocks and soil for the next two years at a dedicated clean room inside Johnson Space Center. The sample will also be divided up and sent to laboratories around the globe, including OSIRIS-REx mission partners at the Canadian Space Agency and Japanese Aerospace Exploration Agency. About 70% of the sample will remain pristine in storage so future generations with better technology can learn even more than what’s now possible. | Chemistry and Material Sciences |
As asteroid expeditions go, NASA's upcoming Psyche mission is about as exciting as they come.
It may not involve saving the planet Earth like Bruce Willis did in the 1998 sci-fi blockbuster Armageddon, but it will be able to tell if a metal-rich space rock has the potential to bring down the world's economy.
That's because the orbiter is due to explore a 4.5 billion-year-old asteroid called 16 Psyche, which scientists think may be packed full of iron, nickel and gold with a value in excess of $10,000 quadrillion (£8,072 quadrillion).
That's enough money to make everyone on the planet a billionaire — although even if NASA is able to confirm this is the case, there are currently no plans to extract the precious metals.
Nevertheless, with the Psyche spacecraft due to launch to space next week, MailOnline has put together a step-by-step guide to everything you need to know ahead of its six-year journey.
When is the launch?
The orbiter is due to piggy-back into space on a SpaceX Falcon Heavy rocket which is scheduled to lift off from Pad 39A at Kennedy Space Center in Florida at 10:16 ET (15:16 BST) on October 12.
The launch was originally scheduled for October 5 but was put back by a week so that engineers could update the configuration of thrusters on the Psyche spacecraft.
About an hour after blast-off, the Falcon Heavy's upper stage will release Psyche on its journey to our solar system's main asteroid belt.
If the mission team encounter any issues which prevent the spacecraft lifting off on October 12, they will have until the launch window closes on October 25 to reschedule.
How can I watch it?
NASA will be streaming the launch live next week.
Its pre-launch coverage without commentary will begin at 09:15 ET (14:15 BST) on the space agency's TV media channel.
The launch broadcast will then begin at 09:30 ET (14:30 BST) on NASA's YouTube, X, Facebook, Twitch and Daily Motion channels.
It will also be shown on the NASA app and the space agency's website.
Two days before the scheduled launch, NASA will also hold a mission and science briefing at 12:00 ET (17:00 BST) on October 10, along with a pre-launch news conference at 13:00 ET (18:00 BST) the following day.
Both will be available to watch on NASA TV, the NASA app and the space agency's website.
No, not for this one. We'll have to wait until the Artemis II mission next year to see astronauts make a journey beyond the International Space Station.
Artemis II will see a four-person crew – made up of Christina Koch, Victor Glover, Reid Wiseman and Canadian astronaut Jeremy Hansen – take a 10-day journey around the moon.
The mission will act as a warm-up for NASA's plan to return humans to the lunar surface by 2025 as part of Artemis III.
This will see the first woman and first person of the colour step foot on the moon.
Where is the orbiter going?
The spacecraft will embark on a six-year, 2.2 billion-mile (3.6 billion-kilometre) trip to a space rock of the same name, 16 Psyche.
This 170-mile-wide (280 kilometre) asteroid sits in the main asteroid belt between Mars and Jupiter.
No spacecraft has ever visited an object like 16 Psyche, but if all goes to plan the orbiter will arrive at its destination in July 2029.
The asteroid is approximately three times farther from the sun than Earth.
However, because Psyche and Earth orbit at different speeds, the distance from us to the space rock varies from less than 186 million miles to more than 372 million miles.
The Psyche spacecraft will actually be using a very efficient propulsion system for the first time beyond the moon, as NASA explains.
'Psyche's system harnesses energy from large solar arrays to create electric and magnetic fields,' the space agency said.
'These, in turn, accelerate and expel charged atoms, or ions, of a propellant called xenon (a neutral gas used in car headlights and plasma TVs) at such high speed, it creates thrust.
'The ionized gas will emit a sci-fi-like blue glow as it trails behind Psyche in space.'
NASA said each of Psyche's four thrusters, operating one at a time, will exert the same amount of force that you would feel holding three coins in the palm of your hand.
'In the frictionless void of space, the spacecraft will slowly and continuously accelerate,' the agency added.
The irregular and potato-like asteroid 16 Psyche is thought to be the exposed core of a demolished protoplanet — the building blocks of worlds such as Earth.
Scientists say the space rock is most likely a survivor of multiple violent hit-and-run collisions, common when the solar system was forming.
During this smash-up and merging of smaller planetesimals, the resulting bigger objects start out completely molten.
Heavy metals the sink to the core, while lighter rock floats to the top.
With 16 Psyche, however, NASA thinks that after reaching this stage it was then hit by another asteroid which stripped it of its rocky mantle and left behind a bare metal core that has been detected today.
Spectroscopic studies and radar observations suggest its surface is up to 95 per cent nickel and iron, a composition similar to that of Earth's core.
The space rock itself was only the 16th asteroid ever discovered, having been spotted in 1852 by Italian astronomer Annibale de Gasparis.
It has an average diameter of some 136 miles (220 kilometres) and contains about 1 per cent the total mass of the entire asteroid belt — around 440 billion billion pounds (220 billion billion kilograms) to be exact.
That makes it among the 12 largest minor planets orbiting the sun between Mars and Jupiter.
Despite its metallic make-up, however, one thing it definitely won't look like is anything resembling what you might find in a jewellery store.
'I would love for it to look like a shiny, polished, what's called a pallasite meteorite — with the shiny silver metal and the beautiful gold and green jewel-like silicate minerals in between,' said Lindy Elkins-Tanton, the mission's principal investigator.
'But it's not going to look like that. Because no one's been onto Psyche, cut it open and polished it.'
She added: 'It's been hanging out in space, getting solar wind hitting it for a really, really long time. So the surfaces are not likely to be shiny.'
Why could it bring down the world's economy?
If 16 Psyche is in fact loaded with precious metals, it could be worth a huge amount of money, according to Dr Linda Elkins-Tanton, a space scientist at MIT.
She has calculated that the iron in 16 Psyche alone would be worth $10,000 quadrillion (£8,072 quadrillion).
Assuming the market for asteroid materials is on Earth, this could cause the value of precious metals to plummet, completely devaluing all holdings including those of governments, and all companies involved in mining, distributing and trading such commodities.
Ultimately, it could lead to the collapse of the entire economy.
Of course it's all speculative and hypothetical, because even if the space rock was worth anywhere close to that kind of money, it's not like it could easily be brought back to Earth and there are currently no plans to do so.
How expensive is the mission?
All in all, it is estimated that the Psyche mission will cost NASA around $1.2 billion (£988 million).
Of this total, $677.1 million (£485.9 million) was for spacecraft development, $112.7 million (£89.4 million) will be spent on the launch, and $171 million (£140.1 million) is set to go on operations during its six-year mission.
NASA's probe is 81ft (25 metres) long and 24ft (7 metres) wide, making it roughly the size of a tennis court with its solar panels extended.
What is the Psyche mission going to do?
Psyche is the first mission to explore an asteroid with a surface that contains substantial amounts of metal rather than rock or ice.
As previously discussed, NASA believes the space rock could consist largely of metal from the core of a planetesimal, one of the building blocks of the rocky planets in our solar system: Mercury, Venus, Earth, and Mars.
If so, it could provide a unique opportunity to study how planets like our own Earth formed.
Scientists believe that rocky planets have dense metal cores at the centre of the magma beneath their surfaces, but because these lie so far beneath the mantle and crust of such worlds, they're difficult to measure and study directly.
That's where the experts hope Psyche will open up possibilities, because they believe it may actually be the exposed core of an early planet.
The spacecraft will carry several instruments, including two high-resolution cameras and a spectrometer to determine the asteroid's composition.
Psyche also has a magnetometer to check if the space rock has a remnant magnetic field, along with an instrument to measure its gravitational field.
It will spend 21 months orbiting the asteroid while capturing the first-ever images of Psyche.
The hope is that by mapping and studying the asteroid in such detail it will help researchers determine how it came to be.
16 Psyche is located in the large asteroid belt between Mars and Jupiter, and may have started as a planet, before it was partially destroyed during the formation of the solar system. Now, it is believed to be a 173 mile (280 km) wide chunk of metal, made up of iron, nickel and a number of other rare metals, including gold, platinum and copper. As such, it offers a unique look into the violent collisions that created Earth and the terrestrial planets. The mission team seeks to determine whether Psyche is the core of an early planet, how old it is, whether it formed in similar ways to Earth's core, and what its surface is like. The spacecraft's instrument payload will include magnetometers, multispectral imagers, and a gamma ray and neutron spectrometer. Why are asteroids worth so much? It may be 230 million miles (370 million km) away from Earth, but this asteroid could be worth a small fortune. 16 Psyche is one of the most mysterious objects in our solar system, and scientists will soon be getting a close-up view thanks to NASA's upcoming mission. If the asteroid could be transported back to Earth, the iron alone that experts think it could contain would be worth $10,000 quadrillion (£8,072 quadrillion). Its value would be large enough to destroy commodity prices and cause the world's economy - worth $73.7 trillion (£59.5 trillion) – to collapse. | Chemistry and Material Sciences |
NASA's Psyche mission to a metal world may reveal the mysteries of Earth's interior
French novelist Jules Verne delighted 19th-century readers with the tantalizing notion that a journey to the center of the Earth was actually plausible.
Since then, scientists have long acknowledged that Verne's literary journey was only science fiction. The extreme temperatures of the Earth's interior—around 10,000 degrees Fahrenheit (5,537 Celsius) at the core—and the accompanying crushing pressure, which is millions of times more than at the surface, prevent people from venturing down very far.
Still, there are a few things known about the Earth's interior. For example, geophysicists discovered that the core consists of a solid sphere of iron and nickel that comprises 20% of the Earth's radius, surrounded by a shell of molten iron and nickel that spans an additional 15% of Earth's radius.
That, and the rest of our knowledge about our world's interior, was learned indirectly—either by studying Earth's magnetic field or the way earthquake waves bounce off different layers below the Earth's surface.
But indirect discovery has its limitations. How can scientists find out more about our planet's deep interior?
Planetary scientists like me think the best way to learn about inner Earth is in outer space. NASA's robotic mission to a metal world is scheduled for liftoff on Oct. 5, 2023. That mission, the spacecraft traveling there, and the world it will explore all have the same name—Psyche. And for six years now, I've been part of NASA's Psyche team.
About the asteroid Psyche
Asteroids are small worlds, with some the size of small cities and others as large as small countries. They are the leftover building blocks from our solar system's early and violent period, a time of planetary formation.
Although most are rocky, icy or a combination of both, perhaps 20% of asteroids are worlds made of metal, and similar in composition to the Earth's core. So it's tempting to imagine that these metallic asteroids are pieces of the cores of once-existing planets, ripped apart by ancient cosmic collisions with each other. Maybe, by studying these pieces, scientists could find out directly what a planetary core is like.
Psyche is the largest-known of the metallic asteroids. Discovered in 1852, Psyche has the width of Massachusetts, a squashed spherical shape reminiscent of a pincushion, and an orbit between Mars and Jupiter in the main asteroid belt. An amateur astronomer can see Psyche with a backyard telescope, but it appears only as a pinpoint of light.
About the Psyche mission
In early 2017, NASA approved the US$1 billion mission to Psyche. To do its work, there's no need for the uncrewed spacecraft to land—instead, it will orbit the asteroid repeatedly and methodically, starting from 435 miles (700 kilometers) out and then going down to 46 miles (75 km) from the surface, and perhaps even lower.
Once it arrives in August 2029, the probe will spend 26 months mapping the asteroid's geology, topography and gravity; it will search for evidence of a magnetic field; and it will compare the asteroid's composition with what scientists know, or think we know, about Earth's core.
The central questions are these: Is Psyche really an exposed planetary core? Is the asteroid one big bedrock boulder, a rubble pile of smaller boulders, or something else entirely? Are there clues that the previous outer layers of this small world—the crust and mantle—were violently stripped away long ago? And maybe the most critical question: Can what we learn about Psyche be extrapolated to solve some of the mysteries about the Earth's core?
About the spacecraft Psyche
The probe's body is about the same size and mass as a large SUV. Solar panels, stretching a bit wider than a tennis court, power the cameras, spectrometers and other systems.
A SpaceX Falcon Heavy rocket will take Psyche off the Earth. The rest of the way, Psyche will rely on ion propulsion—the gentle pressure of ionized xenon gas jetting out of a nozzle provides a continuous, reliable and low-cost way to propel spacecraft out into the solar system.
The journey, a slow spiral of 2.5 billion miles (4 billion km) that includes a gravity-assist flyby past Mars, will take nearly six years. Throughout the cruise, the Psyche team at NASA's Jet Propulsion Laboratory in Pasadena, California, and here at Arizona State University in Tempe, will stay in regular contact with the spacecraft. Our team will send and receive data using NASA's Deep Space Network of giant radio antennas.
Even if we learn that Psyche is not an ancient planetary core, we're bound to significantly add to our body of knowledge about the solar system and the way planets form. After all, Psyche is still unlike any world humans have ever visited. Maybe we can't yet journey to the center of the Earth, but robotic avatars to places like Psyche can help unlock the mysteries hidden deep inside the planets—including our own.
Provided by The Conversation | Chemistry and Material Sciences |
A 3,000-year-old weapon fashioned from 'alien iron' has been found near a lake in Switzerland.
An arrowhead made from a meteorite was recovered at an ancient Bronze Age site called Mörigen, which has produced a trove of space rocks throughout history.
Geologists with the University of Bern tested the artifact's composition, including aluminum-26, a short-lived isotope once abundant in the early solar system - but it is not naturally found on Earth.
However, only three meteorites with the same combination of metals have fallen to Earth around the same time in Europe: One in the Czech Republic, another in Spain, and the third in Estonia.
The team believes the Estonian space rock was the likely candidate, which is more than 1,400 miles from Switzerland.
The arrowhead is 1.5 inches long and weighs only 0.102 ounces.
The team used various methods to test the composition, including electron microscopy pictures, X-rays and high-energy radiation analyses.
The pointed piece was fashioned from an iron meteorite made primarily of kamacite and taenite minerals only found on Earth because they fell from space.
Iron meteorites are derived from the cores of ancient Planets that were destroyed around 4.5 billion years ago by catastrophic impact events during the formation of our Solar System.
'The style of the iron arrowhead strongly resembles that of bronze arrowheads from the same find complex, even though the fabrication process was very different,' the team shared in the study.
'The attached carbon-rich organic material likely represents remnants of tar, probably wood (birch?) tar, indicating that it was fastened to an arrow at some point.'
While the arrowhead was originally found at Lake of Biel sometime during the 19th century, it was tucked away at Bern History Museum, where it was rediscovered and tested.
Researchers initially thought the space rock used to make the weapon came from the Twannberg meteorite that crashed in Switzerland about 160,000 years ago.
However, further analysis of meteorites with the same competition found this was not the case.
'The Mörigen arrowhead must be derived from a large (minimum 2 tons pre-atmospheric mass) IAB iron meteorite based on gamma spectrometry and elemental composition,' reads the study.
'Among large IAB meteorites from Europe, three have a chemical composition consistent with the Mörigen arrowhead: Bohumilitz (Czech Republic), Retuerte de Bullaque (Spain) and Kaalijarv (Estonia).
'Kaalijarv is a large meteorite that produced a series of impact craters (the largest, called Kaalijärv, is 110 m [360 feet] in diameter, note different spelling for meteorite and crater) on the island of Saarema in Estonia.'
The team believes the arrowhead came from Estonia, suggesting people traded the weapons over the same routes from the Baltic area as amber. | Chemistry and Material Sciences |
After months of anticipation, NASA's Psyche mission has finally launched today.
The US space agency launched at 10:19 ET (15:19 BST) from the Kennedy Space Center in Florida.
'Feel the noize! Ain't nothin' but a good time. All aboard the #MissionToPsyche! Next stop: A metal world,' NASA tweeted.
Psyche is a spacecraft built to explore a 4.5 billion-year-old asteroid called 16 Psyche, which scientists think may be packed full of iron, nickel and gold with a value in excess of $10,000 quadrillion (£8,072 quadrillion).
That's enough money to make everyone on Earth a billionaire — although even if NASA is able to confirm this is the case, there are currently no plans to extract the precious metals.
Psyche's launch had already been delayed once, with the $1.2 billion (£988 million) spacecraft originally scheduled to blast into space on October 5, only for this to be put back by a week so that engineers could update the configuration of its thrusters.
When it reached orbit, Psyche will embark on a six-year, 2.2 billion-mile (3.6 billion-kilometre) trip to a space rock of the same name, 16 Psyche.
This 170-mile-wide (280 kilometre) asteroid sits in the main asteroid belt between Mars and Jupiter.
No spacecraft has ever visited an object like 16 Psyche – thought to have a surface containing substantial amounts of metal rather than rock or ice – but if all goes to plan the orbiter will arrive at its destination in July 2029.
The irregular and potato-like asteroid is believed to be the exposed core of a demolished protoplanet — the building blocks of the rocky planets in our solar system: Mercury, Venus, Earth, and Mars.
HOW MUCH IS PSYCHE WORTH? If 16 Psyche is in fact loaded with precious metals, it could be worth an extraordinary amount of money, according to Dr Linda Elkins-Tanton, a space scientist at MIT. She has calculated that the iron in 16 Psyche alone would be worth $10,000 quadrillion (£8,072 quadrillion). Assuming the market for asteroid materials is on Earth, this could cause the value of precious metals to plummet, completely devaluing all holdings including those of governments, and all companies involved in mining, distributing and trading such commodities. Ultimately, it could lead to the collapse of the entire economy. Speaking to Global News Canada, Dr Elkins-Tanton said: 'Even if we could grab a big metal piece and drag it back here … what would you do? 'Could you kind of sit on it and hide it and control the global resource – kind of like diamonds are controlled corporately – and protect your market? 'What if you decided you were going to bring it back and you were just going to solve the metal resource problems of humankind for all time? This is wild speculation obviously.'
If so, it could provide a unique opportunity to study how planets like our own formed.
Scientists say the space rock is most likely a survivor of multiple violent hit-and-run collisions, common when the solar system was forming.
During this smash-up and merging of smaller planetesimals, the resulting bigger objects start out completely molten.
Heavy metals then sink to the core, while lighter rock floats to the top.
With 16 Psyche, however, NASA thinks that after reaching this stage it was then hit by another asteroid which stripped it of its rocky mantle and left behind a bare metal core that has been detected today.
Spectroscopic studies and radar observations suggest its surface is up to 95 per cent nickel and iron, a composition similar to that of Earth's core.
If 16 Psyche is in fact loaded with precious metals, it could be worth a huge amount of money, according to Dr Linda Elkins-Tanton, a space scientist at MIT.
She has calculated that the iron in 16 Psyche alone would be worth $10,000 quadrillion (£8,072 quadrillion).
Assuming the market for asteroid materials is on Earth, this could cause the value of precious metals to plummet, completely devaluing all holdings including those of governments, and all companies involved in mining, distributing and trading such commodities.
Ultimately, it could lead to the collapse of the entire economy.
Of course it's all speculative and hypothetical, because even if the space rock was worth anywhere close to that kind of money, it's not like it could easily be brought back to Earth and there are currently no plans to do so.
16 Psyche was actually only the 16th asteroid ever discovered, having been spotted in 1852 by Italian astronomer Annibale de Gasparis.
It has an average diameter of some 136 miles (220 kilometres) and contains about 1 per cent the total mass of the entire asteroid belt — around 440 billion billion pounds (220 billion billion kilograms) to be exact.
That makes it among the 12 largest minor planets orbiting the sun between Mars and Jupiter.
The Psyche spacecraft will carry with it several instruments, including two high-resolution cameras and a spectrometer to determine the asteroid's composition.
It also has a magnetometer to check if the space rock has a remnant magnetic field, along with an instrument to measure its gravitational field.
The orbiter will spend a total of 21 months orbiting the asteroid while capturing the first-ever images of 16 Psyche.
The hope is that by mapping and studying the asteroid in such detail it will help researchers determine how it came to be, which could in turn shed light on the formation of our own planet. | Chemistry and Material Sciences |
"It's beautiful, it really is - certainly what we've seen of it so far," said Dr Ashley King.
The UK scientist was in a select group to put first eyes and instruments on the rocky samples that have just been brought back from asteroid Bennu.
The materials, scooped up by a US space agency (Nasa) mission and returned to Earth 17 days ago, are currently being examined in a special lab in Texas.
"We've confirmed we went to the right asteroid," Dr King told BBC News.
The three-day analysis by the Natural History Museum (NHM) expert and five others on the "Quick Look" team showed the black, extraterrestrial powder to be rich in carbon and water-laden minerals.
That's a great sign. There's a theory that carbon-rich (organic), water-rich asteroids similar to Bennu may have been involved in delivering key components to the young Earth system some 4.5 billion years ago. It's potentially how we got the water in our oceans and some of the compounds that were necessary to kick-start life.
The asteroid samples will be used to test these ideas.
"We're trying to find out who we are, what we are, where we came from. What is our place in this vastness called the Universe?" said Nasa Administrator Bill Nelson during a briefing at the Johnson Space Center, where the dedicated lab is housed.
Although it's evident the mission has returned an "abundance of sample", scientists are still not sure precisely how much of Bennu they actually have in their possession.
The sample canister which landed in the Utah desert on 24 September has been opened but the inner chamber used by the Osiris-Rex spacecraft to store the asteroid fragments for the journey home has yet to be fully emptied of its contents and weighed.
The mission team thinks it has about 250 grams (9oz) in total. It will take a few more days' careful disassembly to corroborate this estimate.
To perform their initial experiments, Dr King and colleagues used particles that had been spilled from the inner chamber - or Tag-Sam (Touch And Go Sample Acquisition Mechanism) as it's known. This fine Bennu dust coats all the canister's enclosing surfaces.
"When they took the lid off the sample canister, it just revealed this black powder everywhere. It was incredible; it was so exciting," Dr King recalled.
"We were sitting at the time and everybody just stood up and started pointing at the screen. It meant we had lots to play with for the 'quick look'. It made our job easier."
The dust was put in an electron microscope, subjected to X-ray diffraction and infrared spectroscopy techniques and scanned by a computed tomography (CT) machine.
One of the key findings is the presence of that carbon. Lots of it. Close to 5% by weight.
"That's a big deal. When the data came back, there were scientists on the team going 'Wow, oh my God!' said Dr Daniel Galvin, an analyst from Nasa's Goddard Space Flight Center. The quick look team detected both carbonates and more complex organics.
Osiris-Rex principal investigator Dr Dante Lauretta highlighted the samples' water content held in clay minerals.
"They have water locked inside their crystal structure," the cosmochemist from the University of Arizona explained.
"I want to stop and think about what that means. That water - that is how we think water got to the Earth. The reason that Earth is a habitable world - that we have oceans and lakes and rivers and rain - is because clay minerals, like the ones we're seeing from Bennu, landed on Earth 4.5 billion years ago."
The Osiris-Rex spacecraft picked up the Bennu materials in October 2020, using a daring manoeuvre to approach and then "high-five" the asteroid - an operation performed while 330 million km (205 million miles) from Earth.
It then took almost three years, for the Nasa probe to come home and drop off its precious cargo at a restricted military test range a couple of hours' drive west of Salt Lake City.
Once the full sample is extracted, a portion of it will be shared with researchers worldwide. About 100 milligrams is expected to come to the UK to be further worked on by Dr King's department at the NHM, and by collaborators at the Open, Oxford and Manchester universities.
The Osiris-Rex teams aim to have a raft of studies completed in time to report at the Lunar and Planetary Science Conference (LPSC) in March. Two major overview papers are also expected to be published at the same time in the journal Meteoritics & Planetary Science. | Chemistry and Material Sciences |
Metals are everywhere in the Universe, from hot gas giants where it rains molten iron to heavy elements formed as a star goes supernova. Exoplanet GJ 367b one-ups them all. This planet is made of metal.
GJ 367b is an extreme planet. This “super Mercury,” which orbits its star once every 7.7 hours, was first discovered by NASA’s TESS planet hunter in 2015. Now, scientists from the University of Turin in Italy and the Thüringer Landessternwarte in Germany have examined more recent measurements of the planet using ESO’s HARPS spectrograph along with the original TESS observations. They found that this object is almost twice as dense as Earth—which suggests it is most likely made of solid iron.
Even though GJ 367b is now a solid iron planet, it might have once been the core of an ancient rocky planet.
“Thanks to our precise mass and radius estimates, we explored the potential internal composition and structure of GJ 367b, and found that it is expected to have an iron core,” the scientists said in a study recently published in The Astrophysical Journal Letters. It’s just that the core takes up over 90 percent of the planet.
Heavy metal groupie
When GJ 367b was discovered, it was just another exoplanet in a distant star system. TESS had a relatively easy time identifying it because there was not an enormous size difference between it and its star. TESS catches an exoplanet transiting its star when the star dips in brightness, as its light is temporarily blocked by a planet. Some factors make GJ 367b more obvious. Though it is still small in comparison to its star, it is not nearly as small as Earth compared to the Sun, so it blocks more light when it transits. It also orbits dangerously close and mind-blowingly fast.
What wasn’t so obvious yet was what it was made of. Finding out the density of an object based on its mass and radius can give scientists an idea of its composition. TESS measured the radius of GJ 367b based on how much light it obscured. To determine the mass of the planet, the scientists used later radial velocity measurements, which detect the gravitational pull of the planet on its host star.
GJ 367b turned out to be so incredibly dense that it’s 1.85 times the density of Earth, which is roughly in line with that of iron. It is now the densest known planet with a short orbital period and the densest super-Mercury. But how could an entire planet form out of nothing but iron?
Too much headbanging
“It is not clear how a low-mass, high-density planet like GJ 367b forms,” the scientists said in the same study. “Possible pathways may include the formation out of material significantly more iron-rich than thought to be normally present in protoplanetry disks.”
But there are many other possible pathways. All the more probable formation scenarios are based on GJ 367b once having been a rocky planet, not unlike Earth or Mars. Its two companion planets, which orbit farther out, are both rocky planets, so all three may have formed the same way. From there, however, GJ 367b would have had a distinct history that involves it losing its outer, rocky layers and ending up as nearly all core.
The outer layers of GJ 367b were possibly stripped by a collision or series of collisions, which is what is thought to have happened to Mercury. If an object—or enough objects—with the right mass and impact velocity smashed into it, the rocky layers could have been liberated and lost.
Another possibility is the intense radiation GJ 367b faced from orbiting so close to its star that it burned away everything else and left it with nothing but its solid iron core. Outer material could have either sublimated and then been lost to space. GJ 367b might have also experienced some combination of collisions and irradiation to become the metal planet it is.
How it got so close to its star to begin with is also an unanswered question, given it’s unlikely to have formed there. The scientists think that gravitational interactions with other planets could have sent it migrating inward from where it formed.
However GJ 367b turned into a metalhead, further investigations into this planet could eventually tell us more about how rocky planets and planets with short orbital periods form and evolve. It’s always the rebels.
Astrophysical Journal Letters,2023. DOI: 10.3847/2041-8213/ace0c7 | Chemistry and Material Sciences |
Astronomers using archived data from the giant Keck II telescope on Mauna Kea in Hawaii have successfully glimpsed Uranus' infrared aurora for the first time.
Like auroras on Earth, those on Uranus are caused when charged particles riding the solar wind interact with the planet's magnetic field and are funneled along magnetic field lines toward the magnetic poles. As they enter Uranus' atmosphere, the charged particles collide with atmospheric molecules, causing those molecules to glow.
On Earth, the auroral light comes from collisions with oxygen and nitrogen atoms, with the colors mostly red, green and blue. On Uranus, however, the dominant atmospheric gases are hydrogen and helium at much lower temperatures than on Earth. These result in Uranus' auroral glow being predominantly at ultraviolet and infrared wavelengths.
The ultraviolet aurora on Uranus was first seen in 1986 by NASA's Voyager 2 probe, which flew past the planet that year. It's taken nearly 40 years to detect its infrared counterpart.
Using data from the Keck II Near-Infrared Spectrometer (NIRSPEC) taken all the way back in 2006, astronomers led by graduate student Emma Thomas of the University of Leicester in England identified emission lines from the H3+ molecule. H3+ is a trihydrogen cation that contains three protons and only two electrons, meaning it is positively charged.
The Uranus emission was the result of molecular hydrogen being ionized and forming H3+ cations following collisions with charged particles, with the emission creating an infrared auroral glow over the northern magnetic pole. In essence, Thomas' team saw Uranus' northern lights.
"The temperature of all the gas giant planets, including Uranus, are hundreds of degrees Kelvin/Celsius above what models predict if only warmed by the sun, leaving us with the big question of how these planets are so much hotter than expected," said Thomas in a statement. "One theory suggests the energetic aurora is the cause of this, which generates and pushes heat from the aurora down towards the magnetic equator."
Another mystery that the aurorae could help solve is why Uranus' (and Neptune's) magnetic fields are misaligned with their rotational axes by such a large amount — on Uranus the misalignment is 59 degrees. Because auroras trace out the magnetic field structure of a planet, which is coupled to the upper layers (the ionosphere and thermosphere) of the atmosphere, further study could reveal hidden clues as to the origin of this misalignment.
The findings were published on Oct. 23 in the journal Nature Astronomy. | Chemistry and Material Sciences |
The sky is littered with metal pollution from bits of space junk that burn up as they reenter the atmosphere, a new study reveals. This unexpected level of contamination, which will likely rise sharply in the coming decades, could change our planet's atmosphere in ways we still don't fully understand, researchers warn.
The study, published Oct. 16 in the journal PNAS, is part of the National Oceanic and Atmospheric Administration's (NOAA) Stratospheric Aerosol Processes, Budget and Radiative Effects (SABRE) mission, which monitors the levels of aerosols — tiny particles suspended in the air — within the atmosphere.
The team used a research plane, which was fitted with a specialized funnel on its nose cone that captures and analyzes aerosols to sample the stratosphere — the atmosphere's second layer that spans between 7.5 and 31 miles (12 and 50 kilometers) above the planet's surface. The study was designed to detect aerosols covered with "meteor dust" left behind by space rocks that burned up upon entry. Instead, the plane detected high levels of metallic elements contaminating the floating molecules, none of which could be explained by meteors or other natural processes.
The two most surprising elements were niobium and hafnium, which are both rare earth metals used to make technological components such as batteries. The researchers were also puzzled by high levels of aluminum, copper and lithium.
The team had not expected to find these elements in the stratosphere and were initially confused as to where they had come from, study lead author Daniel Murphy, an atmospheric chemist at NOAA's Chemical Sciences Laboratory in Boulder, Colorado, said in a statement. "But the combination of aluminum and copper, plus niobium and hafnium, which are used in heat-resistant, high-performance alloys, pointed us to the aerospace industry," he said.
The discovery "represents the first time that stratospheric pollution has been unquestionably linked to reentry of space debris," researchers wrote in the statement.
In total, the study identified 20 different metallic elements that do not naturally occur in Earth's atmosphere, including silver, iron, lead, magnesium, titanium, beryllium, chromium, nickel and zinc.
The team suspects that the main source of the pollution is rocket boosters that are ejected by rockets shortly after they clear the upper atmosphere, then fall back to Earth.
Pollution from satellites will likely increase as more commercial satellites are launched into space. Of particular concern is the nearly 9,000 satellites that are currently in low-Earth orbit, which are all destined to eventually fall back to Earth, according to Orbiting Now.
In total, around 10% of aerosols from the new study were polluted with space junk metals. But the researchers predict that this could jump to around 50% in the next few decades.
It is currently too early to tell what long-term effects this pollution will have on our planet. But past atmospheric pollution, such as chlorofluorocarbons (CFCs), contributed to holes in the ozone layer. Aerosols also play a role in reflecting sunlight back into space, which is important for mitigating the effects of climate change.
"A lot of work" will be needed to "understand the implications" of these metals in the atmosphere, Murphy said.
Live Science newsletter
Stay up to date on the latest science news by signing up for our Essentials newsletter.
Harry is a U.K.-based staff writer at Live Science. He studied Marine Biology at the University of Exeter (Penryn campus) and after graduating started his own blog site "Marine Madness," which he continues to run with other ocean enthusiasts. He is also interested in evolution, climate change, robots, space exploration, environmental conservation and anything that's been fossilized. When not at work he can be found watching sci-fi films, playing old Pokemon games or running (probably slower than he'd like). | Chemistry and Material Sciences |
About 4.5 billion years ago, a Mars-sized object smashed into the young Earth, spraying debris that coalesced to form the moon, many scientists think. Some remnants of that object, called Theia, exist today as large amounts of dense material sitting atop Earth’s core, researchers propose November 1 in Nature.
In recent years, geophysicists have discovered continent-sized zones of rock at the base of Earth’s mantle where seismic waves travel abnormally slowly, suggesting the rock there is denser than the rest of the mantle rock. One of these blobs, known as large low-velocity provinces, lies beneath Africa. The other lies half a world away beneath the Pacific Ocean, says Qian Yuan, a planetary geodynamicist at Caltech.
Some researchers have suggested these masses are the remnants of tectonic plates that were shoved beneath others and then sunk down to the boundary between Earth’s outer core and the overlying mantle. But Yuan and his colleagues offer a different origin story.
The moon is only about 2 percent the mass of Earth, which leaves a substantial amount of Theia unaccounted for. So, using supercomputer simulations, the researchers tracked the fallout from a smashup between the nascent Earth and another object about 10 percent as massive.
In the simulations, each body before the collision had a dense iron core swaddled by a mantle of lighter rocks. Each object was digitally subdivided into particles about 10 kilometers across, so that the postimpact fragments could be tracked, says study coauthor Vincent Eke, a computational physicist at Durham University in England. In all, the team’s simulations tracked about 100 million particles, he notes.
The simulations suggest that a large part of Theia’s core — equivalent to about 3 percent of Earth’s mass today — was left on our planet. Soon after the collision, that dense molten material would have sunk to join Earth’s core. Meanwhile, a large volume of Theia’s mantle, up to 5 percent of Earth’s mass, was embedded in the uppermost 1,400 kilometers or so of Earth’s mantle, the study finds.
Moon rocks suggest that Theia’s mantle contained higher proportions of iron oxide minerals. That means it was probably a few percent denser than Earth’s mantle, Yuan says. Over the few tens of millions of years that followed the collision, that denser-than-average material slowly sank to accumulate and form the large low-velocity provinces, the researchers suggest.
Although many researchers have suggested that these low-velocity provinces are the remnants of tectonic plates, others have proposed that they’re high-density remnants of Earth’s original magma ocean that sank to the lowermost levels of Earth’s mantle. Attributing them to material left in the wake of the collision between Theia and the nascent Earth “is a new idea, I think,” says Paul Tackley, a geodynamicist at ETH Zurich who was not part of the new study.
Whether or not a run-in with Theia is what created the low-velocity provinces, it’s at least plausible that they’ve lasted the nearly 4.5 billion years since the moon’s formation, Tackley says. If the materials in those zones are dense enough to resist mixing with the overlying mantle as it slowly flows across them, he says, “they can survive over geological time.”
Known as the “giant impact hypothesis,” a collision between Earth and a protoplanet remains the leading theory of how the moon formed. Previously, researchers have suggested that such a collision would help explain the slight chemical differences between moon rocks and Earth’s (SN: 6/5/14). And scientists recently proposed that a collision between the nascent Earth and Theia, besides creating our planet’s moon, also may have jump-started plate tectonics (SN: 3/15/23). | Chemistry and Material Sciences |
Subsets and Splits