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Comet, a small body orbiting the Sun with a substantial fraction of its composition made up of volatile ices. When a comet comes close to the Sun, the ices sublimate (go directly from the solid to the gas phase) and form, along with entrained dust particles, a bright outflowing atmosphere around the comet nucleus known as a coma. As dust and gas in the coma flow freely into space, the comet forms two tails, one composed of ionized molecules and radicals and one of dust. The word comet comes from the Greek κομητης (kometes), which means "long-haired." Indeed, it is the appearance of the bright coma that is the standard observational test for whether a newly discovered object is a comet or an asteroid.
General considerations
Comets are among the most-spectacular objects in the sky, with their bright glowing comae and their long dust tails and ion tails. Comets can appear at random from any direction and provide a fabulous and ever-changing display for many months as they move in highly eccentric orbits around the Sun.
Comets are important to scientists because they are primitive bodies left over from the formation of the solar system. They were among the first solid bodies to form in the solar nebula, the collapsing interstellar cloud of dust and gas out of which the Sun and planets formed. Comets formed in the outer regions of the solar nebula where it was cold enough for volatile ices to condense. This is generally taken to be beyond 5 astronomical units (AU; 748 million km, or 465 million miles), or beyond the orbit of Jupiter. Because comets have been stored in distant orbits beyond the planets, they have undergone few of the modifying processes that have melted or changed the larger bodies in the solar system. Thus, they retain a physical and chemical record of the primordial solar nebula and of the processes involved in the formation of planetary systems.
A comet is made up of four visible parts: the nucleus, the coma, the ion tail, and the dust tail. The nucleus is a solid body typically a few kilometres in diameter and made up of a mixture of volatile ices (predominantly water ice) and silicate and organic dust particles. The coma is the freely escaping atmosphere around the nucleus that forms when the comet comes close to the Sun and the volatile ices sublimate, carrying with them dust particles that are intimately mixed with the frozen ices in the nucleus. The dust tail forms from those dust particles and is blown back by solar radiation pressure to form a long curving tail that is typically white or yellow in colour. The ion tail forms from the volatile gases in the coma when they are ionized by ultraviolet photons from the Sun and blown away by the solar wind. Ion tails point almost exactly away from the Sun and glow bluish in colour because of the presence of CO+ ions.
Comets differ from other bodies in the solar system in that they are generally in orbits that are far more eccentric than those of the planets and most asteroids and far more inclined to the ecliptic (the plane of Earth's orbit). Some comets appear to come from distances of over 50,000 AU, a substantial fraction of the distance to the nearest stars. Their orbital periods can be millions of years in length. Other comets have shorter periods and smaller orbits that carry them from the orbits of Jupiter and Saturn inward to the orbits of the terrestrial planets. Some comets even appear to come from interstellar space, passing around the Sun on open, hyperbolic orbits, but in fact are members of the solar system.
Comets are typically named for their discoverers, though some comets (e.g., Halley and Encke) are named for the scientists who first recognized that their orbits were periodic. The International Astronomical Union (IAU) prefers a maximum of two discoverers to be in a comet's name. In some cases where a comet has been lost (its orbit was not determined well enough to predict its return), the comet is named for the original discoverer and also the observer(s) who found it again. A designation of "C/" before a comet's name denotes that it is a long-period comet (period greater than 200 years), while "P/" denotes that the comet is periodic; i.e., it returns at regular, predictable intervals of fewer than 200 years. A designation of "D/" denotes that the comet is deceased or destroyed, such as D/Shoemaker-Levy 9, the comet whose components struck Jupiter in July 1994. Numbers appearing before the name of a comet denote that it is periodic; the comets are numbered in the order that they are confirmed to be periodic. Comet "1P/Halley" is the first comet to be recognized as periodic and is named after English astronomer Edmond Halley, who determined that it was periodic.
In 1995 the IAU implemented a new identification system for each appearance of a comet, whether it is periodic or long-period. The system uses the year of the comet's discovery, the half-month in the year denoted by a letter A through Y (with I omitted to avoid confusion), and a number signifying the order in which the comet was found within that half-month. Thus, Halley's Comet is designated 1P/1682 Q1 when Halley saw it in August 1682, but 1P/1982 U1 when it was first spotted by astronomers before its predicted perihelion (point when closest to the Sun) passage in 1986. This identification system is similar to that now used for asteroid discoveries, though the asteroids are so designated only when they are first discovered. (The asteroids are later given official catalog numbers and names.) Formerly, a number after the name of a periodic comet denoted its order among comets discovered by that individual or group, but for new comets there would be no such distinguishing number.
Ancient Greece to the 19th century
The Greek philosopher Aristotle thought that comets were dry exhalations of Earth that caught fire high in the atmosphere or similar exhalations of the planets and stars. However, the Roman philosopher Seneca thought that comets were like the planets, though in much larger orbits. He wrote:
The man will come one day who will explain in what regions the comets move, why they diverge so much from the other stars, what is their size and their nature.
Aristotle's view won out and persisted until 1577, when Danish astronomer Tycho Brahe attempted to use parallax to triangulate the distance to a bright comet. Because he could not measure any parallax, Brahe concluded that the comet was very far away, at least four times farther than the Moon.
Brahe's student, German astronomer Johannes Kepler, devised his three laws of planetary motion using Brahe's meticulous observations of Mars but was unable to fit his theory to the very eccentric orbits of comets. Kepler believed that comets traveled in straight lines through the solar system. The solution came from English scientist Isaac Newton, who used his new law of gravity to calculate a parabolic orbit for the comet of 1680. A parabolic orbit is open, with an eccentricity of exactly 1, meaning the comet would never return. (A circular orbit has an eccentricity of 0.) Any less-eccentric orbits are closed ellipses, which means a comet would return.
Newton was friends with English astronomer Edmond Halley, who used Newton's methods to determine the orbits for 24 observed comets, which he published in 1705. All the orbits were fit with parabolas because the quality of the observations at that time was not good enough to determine elliptical or hyperbolic orbits (eccentricities greater than 1). But Halley noted that the comets of 1531, 1607, and 1682 had remarkably similar orbits and had appeared at approximately 76-year intervals. He suggested that it was really one comet in an approximately 76-year orbit that returned at regular intervals. Halley predicted that the comet would return again in 1758. He did not live to see his prediction come true, but the comet was recovered on Christmas Day, 1758, and passed closest to the Sun on March 13, 1759. The comet was the first recognized periodic comet and was named in Halley's honour, Comet Halley.
Halley also speculated whether comets were members of the solar system or not. Although he could only calculate parabolic orbits, he suggested that the orbits were actually eccentric and closed, writing:
For so their Number will be determinate and, perhaps, not so very great. Besides, the Space between the Sun and the fix'd Stars is so immense that there is Room enough for a Comet to revolve tho' the period of its Revolution be vastly long.
The German astronomer Johann Encke was the second person to recognize a periodic comet. He determined that a comet discovered by French astronomer Jean-Louis Pons in 1818 did not seem to follow a parabolic orbit. He found that the orbit was indeed a closed ellipse. Moreover, he showed that the orbital period of the comet around the Sun was only 3.3 years, still the shortest orbital period of any comet on record. Encke also showed that the same comet had been observed by French astronomer Pierre Méchain in 1786, by British astronomer Caroline Herschel in 1795, and by Pons in 1805. The comet was named in Encke's honour, as Comet Halley was named for the astronomer who described its orbit.
Encke's Comet soon presented a new problem for astronomers. Because it returned so often, its orbit could be predicted precisely based on Newton's law of gravity, with effects from gravitational perturbations by the planets taken into account. But Encke's Comet repeatedly arrived about 2.5 hours too soon. Its orbit was slowly shrinking. The problem became even more complex when it was discovered that other periodic comets arrived too late. Those include the comets 6P/D'Arrest, 14P/Wolf 1, and even 1P/Halley, which typically returns about four days later than a purely gravitational orbit would predict.
Several explanations were suggested for this phenomenon, such as a resisting interplanetary medium that caused the comet to slowly lose orbital energy. However, that idea could not explain comets whose orbits were growing, not shrinking. German mathematician and astronomer Friedrich Bessel suggested that expulsion of material from a comet near perihelion was acting like a rocket motor and propelling the comet into a slightly shorter- (or longer-) period orbit each time it passed close to the Sun. History would prove Bessel right.
As the quality of the observations and mathematical techniques to calculate orbits improved, it became obvious that most comets were on elliptical orbits and thus were members of the solar system. Many were recognized to be periodic. But some orbit solutions for long-period comets suggested that they were slightly hyperbolic, suggesting that they came from interstellar space. That problem would not be solved until the 20th century.
Another interesting problem for astronomers was a comet discovered in 1826 by the Austrian military officer and astronomer Wilhelm, Freiherr (baron) von Biela. Calculation of its orbit showed that it, like Encke's Comet, was a short-period comet; it had a period of about 6.75 years. It was only the third periodic comet to be confirmed. It was identified with a comet observed by French astronomers Jacques Lebaix Montaigne and Charles Messier in 1772 and by Pons in 1805, and it returned, as predicted, in 1832. In 1839 the comet was too close in the sky to the Sun and could not be observed, but it was seen again on schedule in November 1845. On January 13, 1846, American astronomer Matthew Maury found that there was no longer a single comet: there were two, following each other closely around the Sun. The comets returned as a pair in 1852 but were never seen again. Searches for the comets in 1865 and 1872 were unsuccessful, but a brilliant meteor shower appeared in 1872 coming from the same direction from which the comets should have appeared. Astronomers concluded that the meteor shower was the debris of the disrupted comets. However, they were still left with the question as to why the comet broke up. That recurring meteor shower is now known as the Andromedids, named for the constellation in the sky where it appears to radiate from, but is also sometimes referred to as the Bielids.
The study of meteor showers received a huge boost on November 12 and 13, 1833, when observers saw an incredible meteor shower, with rates of hundreds and perhaps thousands of meteors per hour. That shower was the Leonids, so named because its radiant (or origin) is in the constellation Leo. It was suggested that Earth was encountering interplanetary debris spread along the Earth-crossing orbits of yet unknown bodies in the solar system. Further analysis showed that the orbits of the debris were highly eccentric.
American mathematician Hubert Newton published a series of papers in the 1860s in which he examined historical records of major Leonid meteor showers and found that they occurred about every 33 years. That showed that the Leonid particles were not uniformly spread around the orbit. He predicted another major shower for November 1866. As predicted, a large Leonid meteor storm occurred on November 13, 1866. In the same year, Italian astronomer Giovanni Schiaparelli computed the orbit of the Perseid meteor shower, usually observed on August 10–12 each year, and noted its strong similarity to the orbit of Comet Swift-Tuttle (109P/1862 O1) discovered in 1862. Soon after, the Leonids were shown to have an orbit very similar to Comet Tempel-Tuttle (55P/1865 Y1), discovered in 1865. Since then the parent comets of many meteoroid streams have been identified, though the parent comets of some streams remains a mystery.
Meanwhile, the study of comets benefitted greatly from the improvement in the quality and size of telescopes and the technology for observing comets. In 1858 English portrait artist William Usherwood took the first photograph of a comet, Comet Donati (C/1858 L1), followed by American astronomer George Bond the next night. The first photographic discovery of a comet was made by American astronomer Edward Barnard in 1892, while he was photographing the Milky Way. The comet, which was in a short-period orbit, was known as D/Barnard 3 because it was soon lost, but it was recovered by Italian astronomer Andrea Boattini in 2008 and is now known as Comet Barnard/Boattini (206P/2008 T3). In 1864 Italian astronomer Giovanni Donati was the first to look at a comet through a spectroscope, and he discovered three broad emission bands that are now known to be caused by long-chain carbon molecules in the coma. The first spectrogram (a spectrum recorded on film) was of Comet Tebbutt (C/1881 K1), taken by English astronomer William Huggins on June 24, 1881. Later the same night, an American doctor and amateur astronomer, Henry Draper, took spectra of the same comet. Both men later became professional astronomers.
Some years before the appearance of Comet Halley in 1910, the molecule cyanogen was identified as one of the molecules in the spectra of cometary comae. Cyanogen is a poisonous gas derived from hydrogen cyanide (HCN), a well-known deadly poison. It was also detected in Halley's coma as that comet approached the Sun in 1910. That led to great consternation as Earth was predicted to pass through the tail of the comet. People panicked, bought "comet pills," and threw "end-of-the-world" parties. But when the comet passed by only 0.15 AU away on the night of May 18–19, 1910, there were no detectable effects.
The modern era
The 20th century saw continued progress in cometary science. Spectroscopy revealed many of the molecules, radicals, and ions in the comae and tails of comets. An understanding began to develop about the nature of cometary tails, with the ion (Type I) tails resulting from the interaction of ionized molecules with some form of "corpuscular radiation," possibly electrons and protons, from the Sun, and the dust (Type II) tails coming from solar radiation pressure on the fine dust particles emitted from the comet.
Astronomers continued to ask, "Where do the comets come from?" There were three schools of thought: (1) that comets were captured from interstellar space, (2) that comets were erupted out of the giant planets, or (3) that comets were primeval matter that had not been incorporated into the planets. The first idea had been suggested by French mathematician and astronomer Pierre Laplace in 1813, while the second came from another French mathematician-astronomer, Joseph Lagrange. The third came from English astronomer George Chambers in 1910.
The idea of an interstellar origin for comets ran into some serious problems. First, astronomers showed that capture of an interstellar comet by Jupiter, the most massive planet, was a highly unlikely event and probably could not account for the number of short-period comets then known. Also, no comets had ever been observed on truly hyperbolic orbits. Some long-period comets did have orbit solutions that were slightly hyperbolic, barely above an eccentricity of 1.0. But a truly hyperbolic comet approaching the solar system with the Sun's velocity relative to the nearby stars of about 20 km (12 miles) per second would have an eccentricity of 2.0.
In 1914 Swedish-born Danish astronomer Elis Strömgren published a special list of cometary orbits. Strömgren took the well-determined orbits of long-period comets and projected them backward in time to before the comets had entered the planetary region. He then referenced the orbits to the barycentre (the centre of mass) of the entire solar system. He found that most of the apparently hyperbolic orbits became elliptical. That proved that the comets were members of the solar system. Orbits of that type are referred to as "original" orbits, whereas the orbit of a comet as it passes through the planetary region is called the "osculating" (or "instantaneous") orbit, and the orbit after the comet has left the planetary region is called the "future" orbit.
The idea of comets erupting from giant planets was favoured by the Soviet astronomer Sergey Vsekhsvyatsky based on similar molecules having been discovered in both the atmospheres of the giant planets and in cometary comae. The idea helped to explain the many short-period comets that regularly encountered Jupiter. But the giant planets have very large escape velocities, about 60 km (37 miles) per second in the case of Jupiter, and it was difficult to understand what physical process could achieve those velocities. So Vsekhsvyatsky moved the origin sites to the satellites of the giant planets, which had far lower escape velocities. However, most scientists still did not believe in the eruption model. The discovery of volcanos on Jupiter's large satellite Io by the Voyager 1 spacecraft in 1979 briefly resurrected the idea, but Io's composition proved to be a very poor match to the composition of comets.
Another idea about cometary origins was promoted by the English astronomer Raymond Lyttleton in a research paper in 1951 and a book, The Comets and Their Origin, in 1953. Because it was known that some comets were associated with meteor showers observed on Earth, the "sandbank" model suggested that a comet was simply a cloud of meteoritic particles held together by its own gravity. Interplanetary gases were adsorbed on the surfaces of the dust grains and escaped when the comet came close to the Sun and the particles were heated. Lyttleton went on to explain that comets were formed when the Sun and solar system passed through an interstellar dust cloud. The Sun's gravity focused the passing dust in its wake, and these subclouds then collapsed under their own gravity to form the cometary sandbanks.
One problem with that theory was that Lyttleton estimated that the gravitational focusing by the Sun would bring the particles together only about 150 AU behind the Sun and solar system. But that did not agree well with the known orbits of long-period comets, which showed no concentration of comets that would have formed at that distance or in that direction. In addition, the total amount of gases that could be adsorbed on a sandbank cloud was not sufficient to explain the measured gas production rates of many observed comets.
In 1948 Dutch astronomer Adrianus van Woerkom, as part of his Ph.D. thesis work at the University of Leiden, examined the role of Jupiter's gravity in changing the orbits of comets as they passed through the planetary system. He showed that Jupiter could scatter the orbits in energy, leading to either longer or shorter orbital periods and correspondingly to larger or smaller orbits. In some cases the gravitational perturbations from Jupiter were sufficient to change the previously elliptical orbits of the comets to hyperbolic, ejecting them from the solar system and sending them into interstellar space. Van Woerkom also showed that because of Jupiter, repeated passages of comets through the solar system would lead to a uniform distribution in orbital energy for the long-period comets, with as many long-period comets ending in very long-period orbits as in very short-period orbits. Finally, van Woerkom showed that Jupiter would eventually eject all the long-period comets to interstellar space over a time span of about one million years. Thus, the comets needed to be resupplied somehow.
Van Woerkom's thesis adviser was the Dutch astronomer Jan Oort, who had become famous in the 1920s for his work on the structure and rotation of the Milky Way Galaxy. Oort became interested in the problem of where the long-period comets came from. Building on van Woerkom's work, Oort closely examined the energy distribution of long-period comet original orbits as determined by Strömgren. He found that, as van Woerkom had predicted, there was a uniform distribution of orbital energies for most energy values. But, surprisingly, there was also a large excess of comets with orbital semimajor axes (half of the long axis of the comet's elliptical orbit) larger than 20,000 AU.
Oort suggested that the excess of orbits at very large distances could only be explained if the long-period comets came from there. He proposed that the solar system was surrounded by a vast cloud of comets that stretched halfway to the nearest stars. He showed that gravitational perturbations by random passing stars would perturb the orbits in the comet cloud, occasionally sending a comet into the planetary region where it could be observed. Oort referred to those comets making their first passage through the planetary region as "new" comets. As the new comets pass through the planetary region, Jupiter's gravity takes control of their orbits, spreading them in orbital energy, and either capturing them to shorter periods or ejecting them to interstellar space.
Based on the number of comets seen each year, Oort estimated that the cloud contained 190 billion comets; today that number is thought to be closer to one trillion comets. Oort's hypothesis was all the more impressive because it was based on accurate original orbits for only 19 comets. In his honour, the cloud of comets surrounding the solar system is called the Oort cloud.
Oort noticed that the number of long-period comets returning to the planetary system was far less than what his model predicted. To account for that, he suggested that the comets were physically lost by disruption (as had happened to Biela's Comet). Oort proposed two values for the disruption rate of comets on each perihelion passage, 0.3 and 1.9 percent, which both gave reasonably good results when comparing his predictions with the actual energy distribution, except for an excess of new comets at near-zero energy.
In 1979 American astronomer Paul Weissman (the author of this article) published computer simulations of the Oort cloud energy distribution using planetary perturbations by Jupiter and Saturn and physical models of loss mechanisms such as random disruption and formation of a nonvolatile crust, based on actual observations of comets. He showed that a very good agreement with the observed energy distribution could be obtained if new comets were disrupted about 10 percent of the time on the first perihelion passage from the Oort cloud and about 4 percent of the time on subsequent passages. Also, comet nuclei developed nonvolatile crusts, cutting off all coma activity, after about 10–100 returns, on average.
In 1981 American astronomer Jack Hills suggested that in addition to the Oort cloud there was also an inner cloud extending inward toward the planetary region to about 1,000 AU from the Sun. Comets are not seen coming from this region because their orbits are too tightly bound to the Sun; stellar perturbations are typically not strong enough to change their orbits significantly. Hills hypothesized that only if a star came very close, even penetrating through the Oort cloud, could it excite the orbits of the comets in the inner cloud, sending a shower of comets into the planetary system.
But where did the Oort cloud come from? At large distances on the order of 104–105 AU from the Sun, the solar nebula would have been too thin to form large bodies like comets that are several kilometres in diameter. The comets had to have formed much closer to the planetary region. Oort suggested that the comets were thrown out of the asteroid belt by close encounters with Jupiter. At that time it was not known that most asteroids are rocky, carbonaceous, or iron bodies and that only a fraction contain any water.
Oort's work was preceded in part by that of the Estonian astronomer Ernst Öpik. In 1932 Öpik published a paper examining what happened to meteors or comets scattered to very large distances from the Sun, where they could be perturbed by random passing stars. He showed that the gravitational tugs from the stars would raise the perihelion distances of most objects to beyond the most distant planet. Thus, he predicted that there would be a cloud of comets surrounding the solar system. However, Öpik said little about the comets returning to the planetary region, other than that some comets could be thrown into the Sun by the stars during their evolution outward to the cloud. Indeed, Öpik concluded:
comets of an aphelion distance exceeding 10,000 a.u., are not very likely to occur among the observable objects, because of the rapid increase of the average perihelion distance due to stellar perturbations.
Öpik also failed to make any comparison between his results and the known original orbits of the long-period comets.
Oort's paper, published in 1950, revolutionized the field of cometary dynamics. Two months later a paper on the nature of the cometary nucleus by Fred Whipple would do the same for cometary physics. Whipple combined many of the ideas of the day and suggested that the cometary nucleus was a solid body made up of volatile ices and meteoritic material. That was called the "icy conglomerate" model but also became more popularly known as the "dirty snowball."
Whipple provided proof for his model in the form of the shrinking orbit of Encke's Comet. Whipple believed that, as Bessel had suggested, rocket forces from sublimating ices on the sunlit side of the nucleus would alter the comet's orbit. For a nonrotating solid nucleus, the force would push the nucleus away from the Sun, appearing to lessen the effect of gravity. But if the comet nucleus was rotating (as most solar system bodies do) and if the rotation pole was not perpendicular to the plane of the comet's orbit, both tangential forces (forward or backward along the comet's direction of motion) and out-of-plane forces (up or down) could result. The effect was helped by the thermal lag caused by the Sun continuing to heat the nucleus surface after local noontime, just as temperatures on Earth are usually at their maximum a few hours after local noon.
Thus, Whipple explained the slow shrinking of Encke's orbit as the result of tangential forces that were pointed opposite to the comet's direction of motion, causing the comet nucleus to slow down, slowly shrinking the orbit. That model also explained periodic comets whose orbits were growing, such as D'Arrest and Wolf 1, depending on the direction of the nuclei's rotation poles and the direction in which the nuclei were rotating. Because the rocket force results from the high activity of the comet nucleus near perihelion, the force does not change the perihelion distance but rather the aphelion distance, either raising or lowering it.
Whipple also pointed out that the loss of cometary ices would leave a layer of nonvolatile material on the surface of the nucleus, making sublimation more difficult, as the heat from the Sun needed to filter down through multiple layers to where there were fresh ices. Furthermore, Whipple suggested that the solar system's zodiacal dust cloud came from dust released by comets as they passed through the planetary system.
Whipple's ideas set off an intense debate over whether the nucleus was a solid body or not. Many scientists still advocated Lyttleton's idea of a sandbank nucleus, simply a cloud of meteoritic material with adsorbed gases. The question would not be put definitively to rest until the first spacecraft encounters with Halley's Comet in 1986.
Solid proof for Whipple's nongravitational force model came from English astronomer Brian Marsden, a colleague of Whipple's at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts. Marsden was an expert on comet and asteroid orbits and tested Whipple's icy conglomerate model against the orbits of many known comets. Using a computer program that determined the orbits of comets and asteroids from observations, Marsden added a term for the expected rocket effect when the comet was active. In this he was aided by Belgian astronomer Armand Delsemme, who carefully calculated the rate of water ice sublimation as a function of a comet's distance from the Sun.
When one calculates an orbit for an object, the calculation usually does not fit all the observed positions of the object perfectly. Small errors creep into the observed positions for many reasons, such as not knowing the exact time of the observations or finding the positions using an out-of-date star catalog. So every orbit fit has a "mean residual," which is the average difference between the observations and the comet's predicted position based on the newly determined orbit. Mean residuals of less than about 1.5 arc seconds are considered a good fit.
When Marsden calculated the comet orbits, he found that he could obtain smaller mean residuals if he included the rocket force in his calculations. Marsden found that for a short-period comet, the magnitude of the rocket force was typically only a few hundred-thousandths of the solar gravitational attraction, but that was enough to change the time when the comet would return. Later, Marsden and colleagues computed the rocket forces for long-period comets and found that there too the mean residuals were reduced. For the long-period comets, the rocket force was typically a few ten-thousandths of the solar gravitational attraction. Long-period comets tend to be far more active than short-period comets, and thus for them the force is larger.
A further interesting result of Marsden's work was that when he performed his calculations on apparently hyperbolic comet orbits, the resulting eccentricities often changed from hyperbolic to elliptical. Very few comets were left with hyperbolic original orbits, and all of those were only slightly hyperbolic. Marsden had provided further proof that all long-period comets were members of the solar system.
In 1951 the Dutch American astronomer Gerard Kuiper published an important paper on where the comets had formed. Kuiper was studying the origin of the solar system and suggested that the volatile molecules, radicals, and ions observed in cometary comae and tails (e.g., CH, NH, OH, CN, CO+, CO2+, N2+) must come from ices frozen in the solid nucleus (e.g., CH4, NH3, H2O, HCN, CO, CO2, and N2). But those ices could only condense in the solar nebula where it was very cold. So he suggested that comets had formed at 38–50 AU from the Sun, where mean temperatures were only about 30–45 K (−243 to −228 °C, or −406 to −379 °F).
Kuiper suggested that the solar nebula did not end at the orbit of what was then considered the most distant planet, Pluto, at about 39 AU, but that it continued on to about 50 AU. He believed that at those large distances from the Sun neither the density of solar nebula material nor the time was enough to form another planet. Rather, he suggested that there would be a belt of smaller bodies—i.e., comets—between 38 and 50 AU. He also suggested that Pluto would dynamically eject comets from that region to distant orbits, forming the Oort cloud.
Astronomers have since discovered that Pluto is too small to have done that job (or even to be considered a planet), and it is really Neptune at 30 AU that defines the outer boundary of the planetary system. Neptune is large enough to slowly scatter comets both inward to short-period orbits and outward to the Oort cloud, along with some help from the other giant planets.
Kuiper's 1951 paper did not achieve the same fame as those by Oort and Whipple in 1950, but astronomers occasionally followed up his ideas. In 1968 Egyptian astronomer Salah Hamid worked with Whipple and Marsden to study the orbits of seven comets that passed near the region of Kuiper's hypothetical comet belt beyond Neptune. They found no evidence of gravitational perturbations from the belt and set upper limits on the mass of the belt of 0.5 Earth masses out to 40 AU and 1.3 Earth masses out to 50 AU.
The situation changed in 1980 when Uruguayan astronomer Julio Fernández suggested that a comet belt beyond Neptune would be a good source for the short-period comets. Up until that time it was thought that short-period comets were long-period comets from the Oort cloud that had dynamically evolved to short-period orbits because of planetary perturbations, primarily by Jupiter. But astronomers who tried to simulate that process on computers found that it was very inefficient and likely could not supply new short-period comets fast enough to replace the existing ones that either were disrupted, faded away, or were perturbed out of the planetary region.
Fernández recognized that a key element in understanding the short-period comets was their relatively low-inclination orbits. Typical short-period comets have orbital inclinations up to about 35°, whereas long-period comets have completely random orbital inclinations from 0° to 180°. Fernández suggested that the easiest way to produce a low-inclination short-period comet population was to start with a source that had a relatively low inclination. Kuiper's hypothesized comet belt beyond Neptune fit this requirement. Fernández used dynamical simulations to show how comets could be perturbed by larger bodies in the comet belt, on the order of the size of Ceres, the largest asteroid (diameter of about 940 km [580 miles]), and be sent into orbits that could encounter Neptune. Neptune then could pass about half of the comets inward to Uranus, with the other half being sent outward to the Oort cloud. In that manner, comets could be handed down to each giant planet and finally to Jupiter, which placed the comets in short-period orbits.
Fernández's paper renewed interest in a possible comet belt beyond Neptune. In 1988 American astronomer Martin Duncan and Canadian astronomers Thomas Quinn and Scott Tremaine built a more complex computer simulation of the trans-Neptunian comet belt and again showed that it was the likely source of the short-period comets. They also proposed that the belt be named in honour of Gerard Kuiper, based on the predictions of his 1951 paper. As fate would have it, the distant comet belt had also been predicted in two lesser-known papers in 1943 and 1949 by a retired Irish army officer and astronomer, Kenneth Edgeworth. Therefore, some scientists refer to the comet belt as the Kuiper belt, while others call it the Edgeworth-Kuiper belt.
Astronomers at observatories began to search for the distant objects. In 1992 they were finally rewarded when British astronomer David Jewitt and Vietnamese American astronomer Jane Luu found an object well beyond Neptune in an orbit with a semimajor axis of 43.9 AU, an eccentricity of only 0.0678, and an inclination of only 2.19°. The object, officially designated (15760) 1992 QB1, has a diameter of about 200 km (120 miles). Since 1992 more than 1,500 objects have been found in the Kuiper belt, some almost as large as Pluto. In fact, it was the discovery of that swarm of bodies beyond Neptune that led to Pluto being recognized in 2006 as simply one of the largest bodies in the swarm and no longer a planet. (The same thing happened to the largest asteroid Ceres in the mid-19th century when it was recognized as simply the largest body in the asteroid belt and not a true planet.)
In 1977 American astronomer Charles Kowal discovered an unusual object orbiting the Sun among the giant planets. Named 2060 Chiron, it is about 200 km (120 miles) in diameter and has a low-inclination orbit that stretches from 8.3 AU (inside the orbit of Saturn) to 18.85 AU (just inside the orbit of Uranus). Because it can make close approaches to those two giant planets, the orbit is unstable on a time span of several million years. Thus, Chiron likely came from somewhere else. Even more interesting, several years later Chiron began to display a cometary coma even though it was still very far from the Sun. Chiron is one of a few objects that appear in both asteroid and comet catalogs; in the latter it is designated 95 P/Chiron.
Chiron was the first of a new class of objects in giant-planet-crossing orbits to be discovered. The searches for Kuiper belt objects have also led to the discovery of many similar objects orbiting the Sun among the giant planets. Collectively they are now known as the Centaur objects. About 300 such objects have now been found, and more than a few also show sporadic cometary activity.
The Centaurs appear to be objects that are slowly diffusing into the planetary region from the Kuiper belt. Some will eventually be seen as short-period comets, while most others will be thrown into long-period orbits or even ejected to interstellar space.
In 1996 European astronomers Eric Elst and Guido Pizarro found a new comet, which was designated 133P/Elst-Pizarro. But when the orbit of the comet was determined, it was found to lie in the outer asteroid belt with a semimajor axis of 3.16 AU, an eccentricity of 0.162, and an inclination of only 1.39°. A search of older records showed that 133P had been observed previously in 1979 as an inactive asteroid. So it is another object that was catalogued as both a comet and an asteroid.
The explanation for 133P was that, given its position in the asteroid belt, where maximum solar surface temperatures are only about −48 °C (−54 °F), it likely acquired some water in the form of ice from the solar nebula. Like in comets, the ices near the surface of 133P sublimated early in its history, leaving an insulating layer of nonvolatile material covering the ice at depth. Then a random impact from a piece of asteroidal debris punched through the insulating layer and exposed the buried ice. Comet 133P has shown regular activity at the same location in its orbit for at least three orbits since it was discovered.
Twelve additional objects in asteroidal orbits have been discovered since that time, most of them also in the outer main belt. They are sometimes referred to as "main belt comets," though the more recently accepted term is "active asteroids."
Spacecraft exploration of comets
The latter half of the 20th century saw a massive leap forward in the understanding of the solar system as a result of spacecraft visits to the planets and their satellites. Those spacecraft collected a wealth of scientific data close up and in situ. The anticipated return of Halley's Comet in 1986 provided substantial motivation to begin using spacecraft to study comets.
The first comet mission (of a sort) was the International Cometary Explorer (ICE) spacecraft's encounter with Comet 21P/Giacobini-Zinner on September 11, 1985. The mission had originally been launched as part of a joint project by the U.S. National Aeronautics and Space Administration (NASA) and the European Space Agency (ESA) known as the International Sun-Earth Explorer (ISEE). The mission consisted of three spacecraft, two of them, ISEE-1 and -2, in Earth orbit and the third, ISEE-3, positioned in a heliocentric orbit between Earth and the Sun, studying the solar wind in Earth's vicinity.
In 1982 and 1983 engineers maneuvered ISEE-3 to accomplish several gravity-assist encounters with the Moon, which put it on a trajectory to encounter 21P/Giacobini-Zinner. The spacecraft was targeted to pass through the ion tail of the comet, about 7,800 km (4,800 miles) behind the nucleus at a relative velocity of 21 km (13 miles) per second, and returned the first in situ measurements of the magnetic field, plasma, and energetic particle environment inside a comet's tail. Those measurements confirmed the model of the comet's ion tail first put forward in 1957 by the Swedish physicist (and later Nobel Prize winner) Hannes Alfvén. It also showed that H2O+ was the most common ion in the plasma tail, consistent with the Whipple model of an icy conglomerate nucleus. However, ICE carried no instruments to study the nucleus or coma of the comet.
In 1986 five spacecraft were sent to encounter Halley's Comet. They were informally known as the Halley Armada and consisted of two Japanese spacecraft, Suisei and Sakigake (Japanese for "comet" and "pioneer," respectively); two Soviet spacecraft, Vega 1 and 2 (a contraction of Venus-Halley using Cyrillic spelling); and an ESA spacecraft, Giotto (named after the Italian painter who depicted the Star of Bethlehem as a comet in a fresco painted in 1305–06).
Suisei flew by Halley on March 8, 1986, at a distance of 151,000 km (94,000 miles) on the sunward side and produced ultraviolet images of the comet's hydrogen corona, an extension of the visible coma seen only in ultraviolet light. It also measured the energetic particle environment in the solar wind ahead of the comet. Sakigake's closest approach to the comet was on March 11, 1986, at a distance of 6.99 million km (4.34 million miles), and it made additional measurements of the solar wind.
Before flying past Halley's Comet, the two Soviet spacecraft had flown by Venus and had each dropped off landers and balloons to study that planet. Vega 1 flew through the Halley coma on March 6, 1986, to within 8,889 km (5,523 miles) of the nucleus and made numerous measurements of the coma gas and dust composition, plasma and energetic particles, and magnetic field environment. It also returned the first picture ever of a solid cometary nucleus. Unfortunately, the camera was slightly out of focus and had other technical problems that required considerable image processing to see the nucleus. Vega 2 fared much better when it flew through the Halley coma on March 9 to within 8,030 km (4,990 miles) of the nucleus, and its images clearly showed a peanut-shaped nucleus about 16 by 8 km (10 by 5 miles) in diameter. The nucleus was also very dark, reflecting only about 4 percent of the incident sunlight, which had already been established from Earth-based observations.
Both Vega spacecraft carried infrared spectrometers designed to measure the temperature of the Halley nucleus. They found quite warm temperatures between 320 and 400 K (47 and 127 °C [116 and 260 °F]). That surprised many scientists who had predicted that the effect of water ice sublimation would be to cool the nucleus's surface; water ice requires a great deal of heat to sublimate. The high temperatures suggested that much of the nucleus's surface was not sublimating, but why?
Whipple's classic paper in 1950 had suggested that as comets lost material from the surface, some particles were too heavy to escape the weak gravity of the nucleus and fell back onto the surface, forming a lag deposit. That idea was later studied by American astronomer and author David Brin in his thesis work with his adviser, Sri Lankan physicist Asoka Mendis, in 1979. As the lag deposit built up, it would effectively insulate the icy materials below it from sunlight. Calculations showed that a layer only 10–100 cm (4–39 inches) in thickness could completely turn off sublimation from the surface. Brin and Mendis predicted that Halley would be so active that it would blow away any lag deposit, but that was not the case. Only about 30 percent of Halley's sunlit hemisphere was active. Bright dust jets could be seen coming from specific areas on the nucleus surface, but much of the surface showed no visible activity.
Giotto flew through Halley's coma on March 14, 1986, and passed only 596 km (370 miles) from the nucleus. It returned the highest-resolution images of the nucleus and showed a very rugged terrain with "mountain peaks" jutting up hundreds of metres from the surface. It also showed the same peanut shape that Vega 2 saw but from a different viewing angle and with much greater visible detail. Discrete dust jets were coming off the nucleus surface, but the resolution was not good enough to reveal the source of the jets.
Giotto and both Vega spacecraft obtained numerous measurements of the dust and gas in the coma. Dust particles came in two types: silicate and organic. The silicate grains were typical of rocks found on Earth such as forsterite (Mg2SiO4), a high-temperature mineral—that is, one which would be among the first to condense out of the hot solar nebula. Analyses of other grains showed that the comet was far richer in magnesium relative to iron. The organic grains were composed solely of the elements carbon, hydrogen, oxygen, and nitrogen and were called CHON grains based on the chemical symbol for each of those elements. Larger grains were also detected that were combinations of silicate and CHON grains, supporting the view that comet nuclei had accreted from the slow aggregation of tiny particles in the solar nebula.
The three spacecraft also measured gases in the coma, water being the dominant molecule but also carbon monoxide accounting for about 7 percent of the gas relative to water. Formaldehyde, carbon dioxide, and hydrogen cyanide were also detected at a few percent relative to water.
The Halley Armada was a rousing success and resulted from international cooperation by many nations. Its success is even more impressive when one considers that the spacecraft all flew by the Halley nucleus at velocities ranging from 68 to 79 km per second (152,000 to 177,000 miles per hour). (The velocities were so high because Halley's retrograde orbit had it going around the Sun in the opposite direction from the spacecraft.)
Giotto was later retargeted using assists from Earth's gravity to pass within about 200 km (120 miles) of the nucleus of the comet 26P/Grigg-Skjellrup. The flyby was successful, but some of the scientific instruments, including the camera, were no longer working after being sandblasted at Halley.
The next comet mission was not until 1998, when NASA launched Deep Space 1, a spacecraft designed to test a variety of new technologies. After flying past the asteroid 9969 Braille in 1999, Deep Space 1 was retargeted to fly past the comet 19P/Borrelly on September 22, 2001. Images of the Borrelly nucleus showed it to be shaped like a bowling pin, with very rugged terrain on parts of its surface and mesa-like formations over a large area of it. Individual dust and gas jets were seen emanating from the surface, but the activity was far less than that of Halley's Comet.
The NASA Stardust mission was launched in 1999 with the goal of collecting samples of dust from the coma of Comet 81P/Wild 2. At a flyby speed of 6.1 km per second (13,600 miles per hour), the dust samples would be completely destroyed by impact with a hard collector. Therefore, Stardust used a material made of silica (sand) called aerogel that had a very low density, approaching that of air. The idea was that the aerogel would slow the dust particles without destroying them, much as a detective might shoot a bullet into a box full of cotton in order to collect the undamaged bullet. It worked, and thousands of fine dust particles were returned to Earth in 2006. Perhaps the biggest surprise was that the sample contained high-temperature materials that must have formed much closer to the Sun than where the comets formed in the outer solar system. That unexpected result meant that material in the solar nebula had been mixed, at least from the inside outward, during the formation of the planets.
Stardust's images of the nucleus of Wild 2 showed a surface that was radically different from either Halley or Borrelly. The surface appeared to be covered with large flat-floored depressions. Those were likely not impact craters, as they did not have the correct morphology and there were far too many large ones. There was some suggestion that it was a very "new" cometary surface on a nucleus that had not been close to the Sun before. Support for that was the fact that Wild 2 had been placed into its current orbit by a close Jupiter approach in 1974, reducing the perihelion distance to about 1.5 AU (224 million km, or 139 million miles). Before the Jupiter encounter, its perihelion was 4.9 AU (733 million km, or 455 million miles), beyond the region where water ice sublimation is significant.
In 2002 NASA launched a mission called Contour (Comet Nucleus Tour) that was to fly by Encke's Comet and 73P/Schwassman-Wachmann 3 and possibly continue on to 6P/D'Arrest. Unfortunately, the spacecraft structure failed when leaving Earth orbit.
In 2005 NASA launched yet another comet mission, called Deep Impact. It consisted of two spacecraft, a mother spacecraft that would fly by Comet 9P/Tempel 1 and a daughter spacecraft that would be deliberately crashed into the comet nucleus. The mother spacecraft would take images of the impact. The daughter spacecraft contained its own camera system to image the nucleus surface up to the moment of impact. To maximize the effect of the impact, the daughter spacecraft contained 360 kg (794 pounds) of solid copper. The predicted impact energy was equivalent to 4.8 tonnes of TNT.
The two spacecraft encountered Tempel 1 on July 4, 2005. The impactor produced the highest-resolution pictures of a nucleus surface ever, imaging details less than 10 metres (33 feet) in size. The mother spacecraft watched the explosion and saw a huge cloud of dust and gas emitted from the nucleus. One of the mission goals was to image the crater made by the explosion, but the dust cloud was so thick that the nucleus surface could not be seen through it. Because the mission was a flyby, the mother spacecraft could not wait around for the dust to clear.
Images of the Tempel 1 nucleus were very different from what had been seen before. The surface appeared to be old, with examples of "geologic" processes having occurred. There was evidence of dust flows across the nucleus surface and what appeared to be two modest-sized impact craters. There was evidence of material having been eroded away. For the first time, icy patches were discovered in some small areas of the nucleus surface.
For the first time, a mission was also able to measure the mass and density of a cometary nucleus. Typically, the nuclei are too small and their gravity too weak to affect the trajectory of the flyby spacecraft. The same was true for Tempel 1, but observations of the expanding dust cloud from the impact could be modeled so as to solve for the nucleus gravity. When combined with the volume of the nucleus as obtained from the camera images, it was shown that the Tempel 1 nucleus had a bulk density between 0.2 and 1.0 gram per cubic centimetre with a preferred value of 0.4 gram per cubic centimetre, less than half that of water ice. The measurement clearly confirmed ideas from telescopic research that comets were not very dense.
After the great success of Stardust and Deep Impact, NASA had additional plans for the spacecraft. Stardust was retargeted to go to Tempel 1 and image the crater from the Deep Impact explosion as well as more of the nucleus surface not seen on the first flyby. Deep Impact was retargeted to fly past 103P/Hartley 2, a small but very active comet.
Deep Impact, in its postimpact EPOXI mission, flew past Comet Hartley 2 on November 4, 2010. It imaged a small nucleus about 2.3 km (1.4 miles) in length and 0.9 km (0.6 mile) wide. As with Halley and Borrelly, the nucleus appeared to be two bodies stuck together, each having rough terrain but covered with very fine, smooth material at the "neck" where they came together. The most amazing result was that the smaller of the two bodies making up the nucleus was far more active than the larger one. The activity on the smaller body appeared to be driven by CO2 sublimation—an unexpected result, given that short-period comets are expected to lose their near-surface CO2 early during their many passages close to the Sun. The other half of the nucleus was far less active and only showed evidence of water ice sublimation. The active half of the comet also appeared to be flinging baseball- to basketball-sized chunks of water ice into the coma, further enhancing the gas production from the comet as they sublimated away.
The EPOXI images also showed that the nucleus was not rotating smoothly but was in complex rotation—a state where the comet nucleus rotates but the direction of the rotation pole precesses rapidly, drawing a large circle on the sky. Hartley 2 was the first encountered comet to exhibit complex rotation. It was likely driven by the very high activity from the smaller half of the nucleus, putting large torques on the nucleus rotation.
Stardust/NExT (New Exploration of Tempel 1) flew past Tempel 1 on February 14, 2011, and it imaged the spot where the Deep Impact daughter spacecraft had struck the nucleus. Some scientists believed that they saw evidence of a crater about 150 metres (500 feet) in diameter, but other scientists looked at the same images and saw no clear evidence of a crater. Some of the ambiguity was due to the fact that the Stardust camera was not as sharp as the Deep Impact cameras, and some of it was also due to the fact that sunlight was illuminating the nucleus from a different direction. The debate over whether there was a recognizable crater lingers on.
Among the new areas observed by Stardust-NeXT there was further evidence of geologic processes, including layered terrains. Using stereographic imaging, the scientists traced dust jets observed in the coma back to the nucleus surface, and they appeared to originate from some of the layered terrain. Again, the resolution of the images was not good enough to understand why the jets were coming from that area.
In 2004 ESA launched Rosetta (named after the Rosetta Stone, which had unlocked the secret of Egyptian hieroglyphics) on a trajectory to Comet 67P/Churyumov-Gerasimenko (67P). Rendezvous with 67P took place on August 6, 2014. Along the way, Rosetta successfully flew by the asteroids 2849 Steins and 21 Lutetia and obtained considerable scientific data. Rosetta uses 11 scientific instruments to study the nucleus, coma, and solar wind interaction. Unlike previous comet missions, Rosetta will orbit the nucleus until December 2015, providing a complete view of the comet as activity begins, reaches a maximum at perihelion, and then wanes. Rosetta carried a spacecraft called Philae that landed on the nucleus surface on November 12, 2014. Philae drilled into the nucleus surface to collect samples of the nucleus and analyze them in situ. As the first mission to orbit and land on a cometary nucleus, Rosetta is expected to answer many questions about the sources of cometary activity.


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I am creating this new thread for daily comments on the market. I know that I have been posting a lot of non-related SIRIUS comments in the Intraday Forum, so I will be posting here. Feel free to post your thoughts here.
I am creating this new thread for daily comments on the market. I know that I have been posting a lot of non-related SIRIUS comments in the Intraday Forum, so I will be posting here. Feel free to post your thoughts here.
Only last night everybody was all worried about Bank of America...it was going to be another dismal day...now their bacon is getting saved and everything is roses and the futures are up! Monday is MLK day and B.O. is going into office.
The big stimulus package is getting passed....thank you Barney Frank! (The same guy that helped murder the economy). He says spend, spend, spend and don't worry about the deficit.
It is only $825 Billion, chump change. I wonder if they have ever heard of inflation? We will need a wheelbarrow to carry enough money to buy a loaf of bread.
Just print the money, don't worry about it being backed up. We can take care of it later. Do you honestly think they will take back the money later?
They just don't get the fact that it is bad credit management that got us into this mess in the first place. I am amazed that we have 500+ Congressman that can be so damn stupid!
I am not being negative or complaining, but I am just observing. What ever it takes to avoid some discomfort and sacrifice is what amazes me. Everything in Washington is done on a knee jerk response. Our forefathers are probably rolling over in their graves. They did things a little bit different...they used to debate issues ahead of time and meet a mutual consensus about what was best for our country.
Next Tuesday, I want my free health care; a chicken in my pot, 27 virgins and our SIRI stock to be at $1.50.
what im hoping to see from obama is simple, making the best choices for the country despite of political leaning, not being a complete tard like bush, a more diplomaticly inclined foreign policy, more regulation of our finanial industries, removal of things liek golden parachutes, hopefully a tax cut for small business's and individuals who need it the most, and the big one legalizing marijuana hah
Last edited by trippingthespeculatingpos; 01-16-2009 at 06:59 PM.
First of all, I loved the ending line there, it was too funny! I hope that you get your pot. It is safer than driving and talking on a cell phone. I made it alive through the 60's and 70's and there is nothing wrong with me, nothing wrong with me, nothing wrong with me..
Now I just drink Maker's Mark (unlike the moonshine I used to drink that tasted like kerosene).
Ya, tripping, I agree with all that you had to say.
I am going to look at the charts tomorrow and try and verify what I think about this supposed rally around B.O..
You know, right at the moment I don't see a rally really building. I am going to run some numbers and check some charts and other stuff. I know that we have had a hell of a financial time here the last few days and some of it was remedied, but I just don't see the momentum.
Everything was all ready overbought and now it is oversold and people are waiting for a bump so they can start shorting again...so I am going to do some investigating this weekend and will make a prediction before Monday.
All of you prediction fans tune in this weekend and see how bad I screw the prediction up for after the holiday!
Have a great evening.
*** Have a great day investors and may your aim be true!***
yeah i tryed to keep it short, i could of gone on all day on what i hope he does lol
I don't think any momentum in the world could beat down the rally that comes Tuesday and Wednesday with Obama taking office. The whole world knows that it is time for a change, and the market will rally because Obama is that change.
I don't think the rally will last, and will probably give back all the gains by Friday, but it might make for a good short term trade.
Yep, Newman, short term at best is my prediction also. I am going to do some research today and try and make a better prediction, but I really agree with you so far.
Being a DC local, I am also excited about the Obama inauguration (but this town is going to be 5 times more disasterous than Bourbon Street at 2am during Mardi Gras).
I am also hopeful that the changes Obama wishes to initiate will work, but the math behind the promises confususes me. Aren't we now just going to be printing a ton more de-valued US Dollars, create an infrastructure of new jobs, which currently don't exist....probably for good reason, while the real nitty gritty of GUARANTEED tax cuts and MANDATORY bank lending to the consumer and to businesses like SIRIUS, which would really stimulate the economy are being left to the wayside. Am I seeing this picture wrong???? I'd love some feedback to help me become more of an optomist!!
I am very hopeful in Obama and his plans.....but at the end of the day, he is only a man (hough a great one) and his plans need to be ratified by a stingy and partisan divided House and Senate.
Let's just hope that they can all play nice in the new Capitol Hill sandbox and get this worlds economy on the right track.
Enjoy the long weekend folks.
here's an interview he did recently, get a chance to hear what he's planning some more i hope, i have yet to watch it though.
I moved this to Obama Honeymoon Rally Predictions thread.
Last edited by billhart22; 01-19-2009 at 11:06 AM. Reason: Moved it to new thread - Obama Honeymoon Rally Predictions


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Even as inflationary pressures nag at our wallets, fresh foods remain a healthy part of the American diet. In fact, consumers in the U.S. spend 30 percent of their food, grocery and personal care expense on fresh foods, according to the Nielsen Global Survey of Fresh Foods. The mix of where consumers shop for fresh, however, is evolving, particularly as retailers learn that customers spend more when there's fresh food in their shopping baskets.
As consumers watch their budgets, value and convenience are important considerations. Although the grocery channel is the leader in fresh foods (accounting for two-thirds of the retail market), fresh is growing in non-grocery channels as retailers respond to consumer demands. In fact, most store expansions since December 2005 have been outside the traditional food, drug and mass merchandise outlets, with the biggest growth occurring among warehouse clubs, supercenters, dollar stores and convenience stores. By 2016, Nielsen expects the retail fresh dollar market share to grow to 15 percent in the hypermarket channel (i.e., combined supermarket/department stores) and to 12 percent in the warehouse club channel.
Americans shop for fresh foods less frequently than shoppers in other regions of the world—1.4 times per week on average, compared with 2.5 times per week globally. Make no mistake however, fresh foods is a high-traffic builder. Savvy retailers understand that consumers want the option to choose fresh foods anywhere, and they're fighting for the fresh share of wallet. "Fresh is becoming more complex with greater variety in products and package sizes, more private label/brand options and increased value-added products, such as diced vegetables or pre-marinated meats," said Bruce Axtman, president, Nielsen Perishables Group. "Understand your shoppers' generational and health needs to tailor offerings and implement programs that best meet their changing demands."
Other notable findings include:
For more detail and insight, download Nielsen's Global Fresh Foods Report.


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When you choose us for an HVAC repair job in Carney, you can trust that your technician will properly adjust your unit to the recommended settings and accurately test the performance of your entire system using specialized tools and advanced testing equipment. Our goal, after all, is to keep your heating and air conditioning system up and running smoothly so that you and your family feel comfortable, all year long. We do so by providing an HVAC repair service that helps clients throughout Carney, MD recover from the following problems:
The methods we choose for HVAC repair depend on which symptoms your unit is exhibiting, whether you've noticed excess noise or unusual odors, and the reasons you're having an issue in the first place. Common causes for HVAC problems like these can range from dirty or clogged filters to blown fuses, worn contactors, and an array of other issues—but our Carney heating and cooling specialists can help you determine the exact cause after assessing your system and discussing your issues with you.
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Imagine you're in a crowded parking lot and don't feel like circling for what seems like hours to find a spot. Now, what if you could tell your car to find its own spot and, even better, command it to pick you up again when you're ready to leave?
That's the promise of Nissan's NSC-2015.
One of the objectives in the design of the car is to "reduce time loss, such as that spent on looking for parking," said Toru Futami, expert leader for Nissan's IT & ITS development department, in a press release.
To that end, after the NSC-2015 uses sensors and a map to gain an awareness of its own location, finds itself a spot, and safely parks in it, its owner can use a smartphone to access an automated valet parking app to summon the car for pick-up when it's time to go.
The car also has an integrated LTE connection that allows its owner to keep track of its status and location via a smartphone. This type of monitoring can come in handy in case someone tries to break into the car, as the camera provides a 360-degree view of what's happening directly outside of it, according to Nissan. In case of a possible intrusion or attempted theft, the NSC-2015's owner can set off the car's alarm remotely.
Nissan isn't the only automaker -- or company, for that matter -- to explore the design of robotic, self-driving cars, which many believe is the future of driving. Car manufacturer and rival Honda debuted its self-driving car in 2009, which helps a human driver do the job.
More famously, a couple of years ago Google demonstrated a self-driving Toyota Prius that, powered by Google software and hardware, could anticipate oncoming traffic, stop signs, or pedestrians in a crosswalk. Rather than go completely driverless, Google's self-driving car, like Honda's, supplements the work of an actual person behind the wheel.
As romantic as a car that drives itself sounds, it will probably be some time before these robotic autos hit the road across the US, as most states still have laws that require someone to actually drive a vehicle for it to be roadworthy.
However, in California, Google's self-driving cars have legally logged hundreds of thousands of miles.
Nissan expects to have its self-parking car on the market by 2015.
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The slowing economy hasn't slowed down one of the top electrical contracting consolidators.
EMCOR Group Inc., Norwalk, Conn., snagged a $100 million, three-year contract to provide comprehensive facilities and maintenance services for all of Bank One's locations nationwide.
EMCOR, which ranked third on CEE News' Top 50 list with electrical sales of $1.37 billion, will provide comprehensive facilities services, including operations, maintenance and supervision, for about 2,200 Bank One facilities, representing 34 million sq ft of space in 30 states.
The EMCOR corporate network of 65 companies will operate and maintain Bank One's building systems, including electrical, plumbing, heating, ventilating and air conditioning systems as well as its other mission-critical systems, and manage the overall property maintenance including janitorial services.
In connection with the agreement, which went into effect July 1, EMCOR has hired about 430 employees, who had previously provided these services at Bank One facilities. This staff will be supplemented by EMCOR's Facilities Services organization, expanding EMCOR's worldwide facilities services personnel to more than 6,300.
Frank MacInnis, chairman and chief executive officer of EMCOR Group, said the award demonstrates EMCOR's ability to leverage its nationwide capabilities.
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Viera Caracara in flight
Discussion in 'Merritt Island VI' started by DW Brewer, Feb 16, 2009.


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Animal Cruelty/Neglect
I have not lived in Madeira for very long, but have on a couple of occasions seen some signs of animal neglect, the worse case with some dogs today.
Whilst I am sure someone will tell me 'when in Rome ......... live as the Romans do", I would not find it impossible to ignore such problems, especially now as I know European laws have been/are being formulated to cover such matters all over Europe.
Is there a body [like the RSPCA in the UK] here to look into cases of animal abuse, or do you have to know on someones door and try and educate them that animals also deserve respect and good treatment?
Thanks for any advice
Whilst I am sure someone will tell me 'when in Rome ......... live as the Romans do", I would not find it impossible to ignore such problems, especially now as I know European laws have been/are being formulated to cover such matters all over Europe.
Is there a body [like the RSPCA in the UK] here to look into cases of animal abuse, or do you have to know on someones door and try and educate them that animals also deserve respect and good treatment?
Thanks for any advice
Hello Der
I like to agreed everting you describe about animal neglect in Madeira! My heart go to special to dogs put in cages like birds cages. Honest god evertime i go to pet chop i am in shock and my heart cry because i can do aninting about.Madeirense people no have idea to be animal lover.
Please Please Alber Joao. Vai aos chops e ve com os seus proprios olhos o que se passa!!!!!!!!!!!!!!!!!!
I am glad samebody start open eyes to madeirense people
On the other hand us British are plainly stupid about animals. We have more cats than dogs when half the world is starving. We throw money at them like there was no tomnorrow. I disgagree with animal cruelty but we (British) are obsessed with animals, here the other week a cat got run over by a car and 2 women outside were in tears at it???? What shall we do they said the driver just sped off. I told them that being as the animal was not on a lead (it was a cat) what did they expect. I stuck it in a bag an dropped it in the bin, end of story. I expect they went home and wore black armbands for a week.
Hi Mariana dont worry your english is better than my Portoguese. I am hoping to learn soon as I plan to move to Maderia next year to start some self catering appartments for tourists. I do not accept cruelty to animals it is uneccessary. All the best Paul maybe talk again if you want to improve your English and me my portoguese. If you want to mail me you can at firstname.lastname@example.com
I agree with you. Some people here are very cruel to dogs and cats. This is an island with an island mentality. People here have not got their dogs as pets, they are watchdogs. It is horrible to see the dogs with too short lead in people's gardens. I have once picked up a puppy that had been thrown out from a window of a car. I really hope that we would have an authority that would deal with the animal cruelty.
But think about it...
What's the point of having a guard dog on a chain? It'll hardly be able to chase any potential thieves, will it?
These dogs are also a menace because they bark all day long because they are so frustrated and unbalanced after years in the same place on a chain often as short as two metres. It really is abominable.
What wil that people do if they where that animal. Look they are not children of God, because they do ugly things. I had people like that, a cat or dog cant talk for them selfs- THEY HAD TO PUT THAT PEOPLE WITHOUT FOOD, WATER OR CLOSE with a chain on the neck outside bind to a tree for ever, and ever.
Thanks for people like you with a hart on the right place
I would never be cruel to an animal but I didn't understand people who really loved animals until I got a cat.
Just a small ball of fur and a pet for my 6 year old daughter. I knew cats were only interested in being fed, would go to who ever did feed them and had no loyalty.
Oh, but that was wrong. I was astonished to find that the cat had emotions! She could be afraid, she could be upset and once when we were out too long and didn't realise we had left her in, she was obviously totally mortified by the puddle she made on the floor. She was jealous and she was oh so faithful. When my husband had an operation that left him bed-bound for weeks, she never left his side except to eat or go to the toilet. When he made a partial recovery and was trying to build up his strength and walk up and down, in great pain and in very bad temper - there she was trying to stand in front of him and stop him - she always knew if we were in pain and always tried to comfort.
My husband hated cats before we got her. I might tell you that this grown man who never shed a tear through all his illness and pain, cried when the cat grew so old that we had to take her to the vet to have her put to sleep because she was in so much pain.
We learned a lot from her. Animals are another form of life every bit as deserving of respect as humans. The fact that we have starving people in this world that we still don't do anything about is no excuse for cruelty to any animal.
I wonder if the people who hold starving children up in front of our eyes as a reason to ignore anumal suffering have ever done more than put some token pennies in a pot?
We should all be horrified by any neglect or cruelty to any form of life. The shame is that most of us don't like to think about it, let alone DO anything about it.
Der, got any ideas?
Thanks Sue and everyone else who replied.
It seems we all agree [well I am not entirely sure about Paul!] that something ought to be done to educate people who do not treat animals with respect, or for something else to be done where people knowingly abuse animals and just don't care.
Unfortunately though, none of the answers has identified an organisation that deals with such matters here on Madeira.
The cruelty and neglect I have seen includes pigs locked in caves all the time, goats and sheep on very short tethers with no more food within reach, and dogs on short leads tied up in the sun all day, or in one case two dogs near Campanario stadium locked in a small shed up to their ankles in their own 'droppings'. On the positive side, the cows on the mountains seem to have a great life though.
So, I don't know what to do? Do the Police have any responsibilities in this matter? I don't have the resources to start anything myself, but would be happy to give up some time to do something positive.
I don't speak much Portuguese myself so I guess my first thought is to ask the Madeira Times newspaper whether it could give the matter some coverage, and then in turn perhaps to the local Portuguese newspapers.
Anyone anymore suggestions, or would anyone want to help?
thanks a lot - Der
OK, I've got something. although it only seems to be for domestic animals:
Sociedade Protectora do Animals Domesticos du Funchal
Rua Matadouro 10-A
9050-100 Funchal
Contact: G N Santos (President)
Tel: 00 351 291 220 852
Fax: 00 351 291 234 643
E-MAIL : email@example.com
They are an associate member of the RSPCA and as such are entitled to received grants from RSPCA.
A Place to start?
Thats good Sue, nice one!
At least we can try and report any problems with dogs and cats etc.
I don't think you would be able to do anything about the farm animals anyway. Even in the UK, most chickens, turkeys, and pigs will never see daylight during their lives and are kept in dreadful conditions, but the vast majority of the UK public don't lose any sleep over that.
Lets see if we can get a bit of free publicity for this contact now.
I read all your mails with great interest. I ahve just returned from a week in Funchal and was amazed to find that all the stray dogs have virtually gone from the streets.
Ssome years ago now, I did everything in my power to try to improve the situation for cats and dogs in Madeira. In this I had no success despite being in contact with the Portuguese Foreign Ministry in Lisbon, and the Internatonal Division of the RSPCA in London, as well as WSPA.
Regarding SPAD - I cannot comment on this on a public website but please contact me privately for more information. You would find it illuminating to pay them a visit!
There is an excellent vet in Funchal, who had plans to open a refuge, but whether he has been able to do this I do not know, have not been in touch with the animal welfare scene for some time, but can give you these contacts:-
Dr Texeira, 61c Carouquera, Funchal. Tel 291 743883 (verterinario)
Mrs Eger 291 774612 (don't know if she is still around, but she used to rescue cats)
Both these people were instrumental in flying homeless animals for rehoming in Germany. I had severe doubts about this and have no idea whether it still goes on.
Do let me know how you get on and if there is anything I can do to help.
Ruth Mayer UK
I found this thread when searching for information on animal welfrae in Madeira.
I have just returned from a fortnight in Funchal with my family and was hoping to gather as much information as possible on contacts in Madeira regarding animal welfare.
Ive just started volunteering at an animal home in North London, the home took in some rescue dogs from Portugal and has already managed to home a few of them. I was hoping that they would be able to do something similar with the dogs in Madeira.
Would you suggest contacting the people mentioned a few messages above?
Any other info would be appreciated!
I know quite well about neglect, some kids kidnaped my dog tortured it threw boiling food on it, and left it to die, we found it because of witbesses, it was so weak it coulden't move and full of tiks, and thin, this isn't the only thing, many hit and run, two boys that grabbed a dog and threw it from their appartememt "to see what would happen" falling into a car making a dent in the car, animal surviving and suffering all the way to the rspca to be put down as they coulden't do anythimng, a girl that has two dogs tied up in a small place with ropes maybe as long as my arm, an owner that keeps her husky in a cage and feeds it now and then leaving food though a week never changing it the excuse " it didn't finish what I put, I'm waitting for it to finish it" even though it is all moldy, I told the rspca about the husky, they seemed very interrested, that was a few months ago, so far nothing happened, dog is still there, noone came.... Epoeple act like they care yet turn their heads the other way! Horrible things, burning animals alive, experementing on them for own fun, putting them to fight, people are starting that, now people with certan dogs need insurance and pay quite a lot, stupid shoulden't they check the dogs not by vreed but attitude, as there can be a tame loving rotweller and a horrible biting mut... maybe the owners should be testes, irresponsible owners shoulden't have dangerous dogs in the fisrt place, a caracter test.... they have parks that they don't want to allpw dogs in then they wonder why dogs are locked inside houses and tied... a big boxer that attacked my mut, and tried to bite its head, luckly I deffended him, and the boxer stoped still looking at my dog as a treat, still loose and at the same place imagine a child goes past and it mistakes it for a dog... I emailed funchal camara, nothing seemed to be done....
Simply irresponsible people, they say you know a place by the way they treat their animals,in that case... well I better not continue!
The following site is a good start to get help on protecting animals in Portugal: http://www.ceda-online.org/ligacoes/
Any police station should be able to investigate animal cruelty as covered by law.
Going to the portuguese television stations will definitely help.
Good luck.
After my second visit to Maderia in1995 the stray dos on the streets upset me very much that I contacted the Portuges embassy Ihave several letters from them stating that they were going to build kennels and start a sterilisation campaign that was1995 its now 2005 I have been thinking about going back this year but what I have just read I think not
Hello all,
During my time in the UK [before moving to Madeira] I spent the last five years volunteering at the Mayhew Animal Home. I fostered cats,kittens dogs and puppies.
I have done many home visits both pre and post. I have interviewed people turning up at the home wanting to adopt animals.
Of course when I came here on holiday I was sorry for the many stray cats and dogs. One of which we had to take to the vet at VetFunchal to have it's tail amputated and it to be spayed and aborted. He also took out some terrible bad teeth. This cat went to Mrs. Eger for re-habilitation and finally went to Germany.
We donated money to Dr. Teixeira's SOS Animal Fund and then we moved to Madeira.
We have lived here 18 months and during that time I [my husband goes back to the UK to work] have been involved in the saving of strays and this is my position now.
Two dogs have been sent to Germany and one has been rehomed here with an English couple. Other people do what they can and I know some other puppies have been re-homed.
Today I have some dogs on a beach who I feed regularly, three were neutered. Somehow they just seem to dissappear. I started with 5, two adults and three puppies. Then another of my 'known' males arrived, then one of the puppies didn't come any more. After neutering the two females and one male we took them back to the beach and only one puppy was left.
Since then only two dogs are now there. Just the male and female of those three we neutered. We were going to get the puppy neutered because it is also a female.
I then had to 'bring in' another dog which was in the mountains because althbough it was seen 6 weeks previously and looked healthy, this time it was extremely thin and had a damaged eye.
We got this dog castrated [all via collections I have made for SOS] and have just yesterday put him back where we found him with the view to feeding him where he knows. I spent a sleepless night worrying for him and this morning went to feed him, he was fine but he then chased after my car. I am devestated but I cannot keep them all. I have four dogs and four cats already.
The organisation SPAD do not have a good record for looking after cruelty cases, the European law which is coming into effect will not affect anything because although the police should be able to investigate cruelty cases they can do nothing about them as they don't have any facilities to keep confiscated animals in and protect them.
I have a need of volunteers who will go regularly to areas to feed animals, the stray animals are sometimes better off than those that are continually tied to small chains. At least if their life is short they have enjoyed liberty.
Some of the animals I feed would not thank you for finding them a home, it is normally only the cute small dogs who are found homes in other countries. The dog I took back to the mountains is not your normal cute small dog and he is 9 months old and only has one eye. I decided this was not a dog who would be easily homeable and decided thebest thing was to take him back where we found him, he has fresh water available and I take food to him.
Anyway, sorry this is such a long post, I am looking for people here in Madeira to the west in Calheta or thereabouts who could offer practical hels. Feeding dogs in 'feeding areas' and also to hold dogs who will go to Germany and need time to get the papers and injections and tests done.
I was in Madeira last week and was concerned to see about 6 cats (feral I think) in the Bird Garden next to the Botanical Gardens in Funchal. Someone was kindly feeding them but the ginger one was in urgent need of medical attention.
I didn't know if there was anything like the RSPCA in Madeira who would be able to help it.
I am surprised at all the opinions expressed in your correspondence about Madeira, about animal cruelty on the island, about Madeirans, about SPAD, the animal protection society in Madeira. You are all invited to visit our installations at Rua do Matadouro 10 A, Funchal, or to visit the municipal kennel managed by SPAD, or if that is too much to ask, visit our website www.spadfnc.org , please be so kind as to also browse the Portuguese site because the English site is only a summary of our work. We are associated to the RSPCA for 2 years now and had two unannounced inspections from them already. We also received financial grants twice from the RSPCA International Department in the last 3 years. I trust you all value the opinion of the RSPCA and just may be you could use all this energy you clearly manifested in favour of helping us or to combine efforts in favour of the animals on our beautiful island. Your judgement is cruel and unfounded and very much outdated. Ten years ago, most of it might have been true, but a lot can change in 10 years...Please be so kind as to get informed because ignorance can be cured.
Kind regards,
Suzette Mariana Steyn
Administrator of SPAD
I once reported to Madeira Times about how a dog was unfairly caged in an "educational park". Having a dog in Holland where I worked, I started searching for places over Madeira where my dog, Didi, could run free and wild as he does in the most pet-friendly Western Europe. Disappointing was I to find that most places, from levadas to beaches, barred dogs.
Can anyone suggest of places where dogs may have their fair share of outdoor life over Madeira? I am bringing my Didi to stay on this lovely island for quite some time.
I would not leave my pets out of their leash at any time in the Island unless in one's private yard. I hear lots of pets have died due to poison or similar. I too am a local citizen but was fortunate to emigrate from the Island long ago, am very against animal cruelty, its all down to educating the locals which they're still long way to go and don't know any better, sadly due to ignorance also. Our local Goverment does not give/never did a toss about it's citizens welfare never mind the animals.
I found this old post on search
we are from madeira living in uk. i report a few times to local madeira dayly paper about animal life in madeira. For last two years the local goverment and funchal council are doing a very goor job in colecting street aninals and also try to find homes and also going to local shoping centers, and making shore that locals adopt and give a nice home. but needs time a and also money to make a change. I like to thank locals and visitors for helping this lovelly cause.
to make a start visit the dog and cat shelter in funchal,rua do matadouro n.10a,9050-100 funchal or you an donate at the web site www.spadfnc.org.
joao correia
Hello to all,
we are urgently searching for help/advice regarding a kitty (male) that we wanted to save on Madeira. We found the cat in front of the Pestana Grand hotel, who was meowing at us and then cuddling with us but seemed quite skinny and hungry. We called SPAD to ask them how to adopt the kitty but unfortunately there was a vaccination that requires 21 days of quarantine and since we were flying back the next day, we were not able to take the cat with us. So we asked them later how else can we help the cat and they said "Well you can bring him/her to the shelter for adoption". So that´s what we did on 19.12.2012 and we also donated money to the shelter. Later on at the end of the day we had doubts about it after searching more info on the internet (non castrating of male cats there, or terrifying information abut having to put some animals down if there is not enough space ?!? Maybe they are keeping the cat in cages?). Therefore we want to help the cat to find an owner and help to get out him out of the shelter as soon as possible.
PLEASE, HELP US TO FIND THIS AMAZING CAT AN OWNER. It breaks our hearts to leave him there.
We will be very happy for any advice or sharing of this information. The cat is a young male, very sweet and cute. He is awaiting you in the animal shelter called SPAD, address is rua de Matadouro 10, FUNCHAL.
He is registered under name CHRISSIE. We are also attaching photos of the kitty.
Thank you so much in advance....
Chris and Domi


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Hubble Images 30 Doradus: the Effects of Massive Stars in R136
This region resembles a coral reef, but the gas has been eroded by the hefty stars in R136, situated above it. Cloaked in gas at the top of this rugged, gaseous terrain are nascent stars that cannot be seen. Dense columns of gas, several light-years long, protrude from the undulating landscape. These gaseous columns are incubators for developing stars.
30 Doradus is the brightest, nearby star-forming region and home to the most massive stars in our cosmic neighborhood of about 25 galaxies. The nebula is close enough to Earth that Hubble can resolve individual stars, giving astronomers important information about the stars' birth and evolution. 30 Doradus resides 170,000 light-years away in the Large Magellanic Cloud, a small, satellite galaxy of our Milky Way.
NASA, ESA, D. Lennon and E. Sabbi (ESA/STScI), J. Anderson, S. E. de Mink, R. van der Marel, T. Sohn, and N. Walborn (STScI), N. Bastian (Excellence Cluster, Munich), L. Bedin (INAF, Padua), E. Bressert (ESO), P. Crowther (University of Sheffield), A. de Koter (University of Amsterdam), C. Evans (UKATC/STFC, Edinburgh), A. Herrero (IAC, Tenerife), N. Langer (AifA, Bonn), I. Platais (JHU), and H. Sana (University of Amsterdam)


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Paper folders are always handy for any enterprise - including schools, print shops, quick-copy centers, banks and mail-houses - as they are great for folding pamphlets, statements, invoices and correspondence. Usually, paper folders can fold anywhere from 4,000 to 115,000 sheets per hour depending on the model of the machine. Different types of folders are available in the … [Read more...]
You are here: Home / Archives for Paper Handing


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June 2001
Test Pilot Collective
|What the heck are Firstpages? They are the same thing as a splashpage. The first Firstpage was on January 1, 1999 when the new Test Pilot Collective site was launched. It's been updated daily for the past 5 years now.
Due to the various sizes of the Firstpages, I've had to crop some of them to fit on this site. If you would like to see them in all their glory, go to Test Pilot Collective. Enjoy!


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1016 Philadelphia Pike, Wilmington, DE 19809
Capacity: 50 - 75. Tented: up to 200. This charming Colonial Revival-style home and summer estate sits gracefully atop a hill on 44 rolling acres, overlooking the Delaware River. Visitors easily forget they are just minutes from downtown Wilmington. Vintage sun porches open onto rolling manicured lawns with picturesque landscaping, a cozy gazebo and spectacular views from every angle of the property. In addition to a formal parlor and dining room, this grand home includes three period bedrooms to accommodate up to six overnight guests. Situated within walking distance from the house is the Cauffiel Barn, a rustic alternative in an elegant setting.


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Apple-Themed Playlist
View original content here
The apple harvest inspired our apple-themed playlist. Enjoy!
Caramel Apples – "Lost" – Coldplay & Jay-Z
Only Coldplay's Chris Martin & foodie wife Gwyneth Paltrow could get away with naming their daughter Apple. Is it because they are crazy for Caramel Apples? I think so. Take a listen to this great track with a guest appearance by Jay-Z, and try your best not to get your hands sticky with this great recipe.
Get the Recipe: Carmel Apples
Hear the Track on Spotify: "Lost" – Coldplay & Jay-Z
Honey-Glaze Apple Pear Tart (pictured at top) – "Tupelo Honey" – Van Morrison
This sweet dessert is almost as enticing as this classic track from the incomparable Van Morrison. The song about love, devotion and dedication is epic and will make your lady swoon — especially after she tastes Kelsey Nixon's amazing pastry.
Get the Recipe: Honey-Glaze Apple Pear Tart
Hear the Track on Spotify: "Tupelo Honey" – Van Morrison
Cheddar Cheese Apple Pie – "American Pie" – Don McLean
Don McLean's signature song about the 1959 plane crash that killed Buddy Holly, Ritchie Valens and The Big Bopper is an integral part of American musical history. Some may think it's a little cheesy, so why not sing along while preparing this Cheddar Cheese Apple Pie.
Get the Recipe: Cheddar Cheese Apple Pie
Hear the Track on Spotify: "American Pie" – Don McLean
Apple Muffins – "Everyday" – Fiona Apple
Speaking of Buddy Holly, this is a personal favorite of mine. And one of my favorite Apples (Fiona, that is) did a touching rendition of his sweet love song "Everyday." Get ready to bake some tasty Apple Muffins and enjoy this taste of the 1950s re-worked by one of today's most critically acclaimed singer/songwriters.
Get the Recipe: Apple Muffins
Hear the Track on Spotify: "Everyday" – Fiona Apple
Apple Rub – "Apple Blossom" – The White Stripes
Simple and sweet, this recipe for Apple Rub is great for all varieties of meat. And in the five minutes of total time it requires, you can listen to this simple and sweet track by the White Stripes twice.
Get the Recipe: Apple Rub
Hear the Track on Spotify: "Apple Blossom" – The White Stripes
Chicken Breasts with Apple-Curry Sauce – "Apple Scruffs" – Carlitos Ordax tribute to George Harrison
"Apple Scruffs" is one of the lesser-known tracks on George Harrison's classic 1970 triple album All Things Must Pass. Apple Scruffs refer to the legions of Beatles fans who would wait at random locations in London hoping to grab a glimpse of the Fab Four. This great rendition of the song can be found on the 2006 Harrison tribute album Thanks For The Pepperoni, released five years after his death. Enjoy this track while preparing Chicken Breasts with Apple-Curry Sauce. Harrison was probably a big fan of curry after spending so much time embracing Indian culture and Hinduism.
Get the Recipe: Chicken Breasts with Apple-Curry Sauce
Hear the Track on Spotify: "Apple Scruffs" – Carlitos Ordax
Applesauce Apple Tart – "New York City's Killing Me" – Ray LaMontagne
It's impossible to do an "apple" list without some kind of tribute to the Big Apple. There were so many choices here, but I went with Ray Lamontagne's "New York City's Killing Me." New York City isn't for everyone, but this recipe for Applesauce Apple Tart would likely be enjoyed by most people.
Get the Recipe: Applesauce Apple Tart
Hear the Track on Spotify: "New York City's Killing Me" – Ray LaMontagne