X-ray astronomy is an observational branch of astronomy which deals with the study of X-ray observation and detection from astronomical objects.  X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites.  X-ray astronomy uses a type of space telescope that can see x-ray radiation which standard optical telescopes, such as the Mauna Kea Observatories, cannot.

X-ray emission is expected from astronomical objects that contain extremely hot gases at temperatures from about a million kelvin (K) to hundreds of millions of kelvin (MK). Moreover, the maintenance of the E-layer of ionized gas high in the Earth's thermosphere also suggested a strong extraterrestrial source of X-rays. Although theory predicted that the Sun and the stars would be prominent X-ray sources, there was no way to verify this because Earth's atmosphere blocks most extraterrestrial X-rays. It was not until ways of sending instrument packages to high altitudes were developed that these X-ray sources could be studied.

The existence of solar X-rays was confirmed early in the mid-twentieth century by V-2s converted to sounding rockets, and the detection of extra-terrestrial X-rays has been the primary or secondary mission of multiple satellites since 1958. The first cosmic (beyond the Solar System) X-ray source was discovered by a sounding rocket in 1962. Called Scorpius X-1 (Sco X-1) (the first X-ray source found in the constellation Scorpius), the X-ray emission of Scorpius X-1 is 10,000 times greater than its visual emission, whereas that of the Sun is about a million times less. In addition, the energy output in X-rays is 100,000 times greater than the total emission of the Sun in all wavelengths.

Many thousands of X-ray sources have since been discovered. In addition, the intergalactic space in galaxy clusters is filled with a hot, but very dilute gas at a temperature between 100 and 1000 megakelvins (MK). The total amount of hot gas is five to ten times the total mass in the visible galaxies.

Sounding rocket flights

The first sounding rocket flights for X-ray research were accomplished at the White Sands Missile Range in New Mexico with a V-2 rocket on January 28, 1949. A detector was placed in the nose cone section and the rocket was launched in a suborbital flight to an altitude just above the atmosphere. X-rays from the Sun were detected by the U.S. Naval Research Laboratory Blossom experiment on board.

An Aerobee 150 rocket launched on June 19, 1962 (UTC) detected the first X-rays emitted from a source outside our solar system (Scorpius X-1). It is now known that such X-ray sources as Sco X-1 are compact stars, such as neutron stars or black holes. Material falling into a black hole may emit X-rays, but the black hole itself does not. The energy source for the X-ray emission is gravity. Infalling gas and dust is heated by the strong gravitational fields of these and other celestial objects. Based on discoveries in this new field of X-ray astronomy, starting with Scorpius X-1, Riccardo Giacconi received the Nobel Prize in Physics in 2002.

The largest drawback to rocket flights is their very short duration (just a few minutes above the atmosphere before the rocket falls back to Earth) and their limited field of view. A rocket launched from the United States will not be able to see sources in the southern sky; a rocket launched from Australia will not be able to see sources in the northern sky.

X-ray Quantum Calorimeter (XQC) project

In astronomy, the interstellar medium (or ISM) is the gas and cosmic dust that pervade interstellar space: the matter that exists between the star systems within a galaxy. It fills interstellar space and blends smoothly into the surrounding intergalactic medium. The interstellar medium consists of an extremely dilute (by terrestrial standards) mixture of ions, atoms, molecules, larger dust grains, cosmic rays, and (galactic) magnetic fields. The energy that occupies the same volume, in the form of electromagnetic radiation, is the interstellar radiation field.

Of interest is the hot ionized medium (HIM) consisting of a coronal cloud ejection from star surfaces at 106-107 K which emits X-rays. The ISM is turbulent and full of structure on all spatial scales. Stars are born deep inside large complexes of molecular clouds, typically a few parsecs in size. During their lives and deaths, stars interact physically with the ISM. Stellar winds from young clusters of stars (often with giant or supergiant HII regions surrounding them) and shock waves created by supernovae inject enormous amounts of energy into their surroundings, which leads to hypersonic turbulence. The resultant structures are stellar wind bubbles and superbubbles of hot gas. The Sun is currently traveling through the Local Interstellar Cloud, a denser region in the low-density Local Bubble.

To measure the spectrum of the diffuse X-ray emission from the interstellar medium over the energy range 0.07 to 1 keV, NASA launched a Black Brant 9 from White Sands Missile Range, New Mexico on May 1, 2008. The Principal Investigator for the mission is Dr. Dan McCammon of the University of Wisconsin–Madison.

Balloons

Balloon flights can carry instruments to altitudes of up to 40 km above sea level, where they are above as much as 99.997% of the Earth's atmosphere. Unlike a rocket where data are collected during a brief few minutes, balloons are able to stay aloft for much longer. However, even at such altitudes, much of the X-ray spectrum is still absorbed. X-rays with energies less than 35 keV (5,600 aJ) cannot reach balloons. On July 21, 1964, the Crab Nebula supernova remnant was discovered to be a hard X-ray (15–60 keV) source by a scintillation counter flown on a balloon launched from Palestine, Texas, United States. This was likely the first balloon-based detection of X-rays from a discrete cosmic X-ray source.

High-energy focusing telescope

The high-energy focusing telescope (HEFT) is a balloon-borne experiment to image astrophysical sources in the hard X-ray (20–100 keV) band. Its maiden flight took place in May 2005 from Fort Sumner, New Mexico, USA. The angular resolution of HEFT is c. 1.5'. Rather than using a grazing-angle X-ray telescope, HEFT makes use of a novel tungsten-silicon multilayer coatings to extend the reflectivity of nested grazing-incidence mirrors beyond 10 keV. HEFT has an energy resolution of 1.0 keV full width at half maximum at 60 keV. HEFT was launched for a 25-hour balloon flight in May 2005. The instrument performed within specification and observed Tau X-1, the Crab Nebula.

High-resolution gamma-ray and hard X-ray spectrometer (HIREGS)
A balloon-borne experiment called the High-resolution gamma-ray and hard X-ray spectrometer (HIREGS) observed X-ray and gamma-rays emissions from the Sun and other astronomical objects. It was launched from McMurdo Station, Antarctica in December 1991 and 1992. Steady winds carried the balloon on a circumpolar flight lasting about two weeks each time.

Rockoons

The rockoon, a blend of rocket and balloon, was a solid fuel rocket that, rather than being immediately lit while on the ground, was first carried into the upper atmosphere by a gas-filled balloon. Then, once separated from the balloon at its maximum height, the rocket was automatically ignited. This achieved a higher altitude, since the rocket did not have to move through the lower thicker air layers that would have required much more chemical fuel.

The original concept of "rockoons" was developed by Cmdr. Lee Lewis, Cmdr. G. Halvorson, S. F. Singer, and James A. Van Allen during the Aerobee rocket firing cruise of the  on March 1, 1949.

From July 17 to July 27, 1956, the Naval Research Laboratory (NRL) shipboard launched eight Deacon rockoons for solar ultraviolet and X-ray observations at ~30° N ~121.6° W, southwest of San Clemente Island, apogee: 120 km.

X-ray astronomy satellite

X-ray astronomy satellites study X-ray emissions from celestial objects. Satellites, which can detect and transmit data about the X-ray emissions are deployed as part of branch of space science known as X-ray astronomy. Satellites are needed because X-radiation is absorbed by the Earth's atmosphere, so instruments to detect X-rays must be taken to high altitude by balloons, sounding rockets, and satellites.

X-ray telescopes and mirrors

X-ray telescopes (XRTs) have varying directionality or imaging ability based on glancing angle reflection rather than refraction or large deviation reflection.
This limits them to much narrower fields of view than visible or UV telescopes. The mirrors can be made of ceramic or metal foil.

The first X-ray telescope in astronomy was used to observe the Sun. The first X-ray picture (taken with a grazing incidence telescope) of the Sun was taken in 1963, by a rocket-borne telescope. On April 19, 1960, the very first X-ray image of the sun was taken using a pinhole camera on an Aerobee-Hi rocket.

The utilization of X-ray mirrors for extrasolar X-ray astronomy simultaneously requires:
 the ability to determine the location at the arrival of an X-ray photon in two dimensions and
 a reasonable detection efficiency.

X-ray astronomy detectors

X-ray astronomy detectors have been designed and configured primarily for energy and occasionally for wavelength detection using a variety of techniques usually limited to the technology of the time.

X-ray detectors collect individual X-rays (photons of X-ray electromagnetic radiation) and count the number of photons collected (intensity), the energy (0.12 to 120 keV) of the photons collected, wavelength (c. 0.008–8 nm), or how fast the photons are detected (counts per hour), to tell us about the object that is emitting them.

Astrophysical sources of X-rays

Several types of astrophysical objects emit, fluoresce, or reflect X-rays, from galaxy clusters, through black holes in active galactic nuclei (AGN) to galactic objects such as supernova remnants, stars, and binary stars containing a white dwarf (cataclysmic variable stars and super soft X-ray sources), neutron star or black hole (X-ray binaries). Some Solar System bodies emit X-rays, the most notable being the Moon, although most of the X-ray brightness of the Moon arises from reflected solar X-rays. A combination of many unresolved X-ray sources is thought to produce the observed X-ray background. The X-ray continuum can arise from bremsstrahlung, black-body radiation, synchrotron radiation, or what is called inverse Compton scattering of lower-energy photons by relativistic electrons, knock-on collisions of fast protons with atomic electrons, and atomic recombination, with or without additional electron transitions.

An intermediate-mass X-ray binary (IMXB) is a binary star system where one of the components is a neutron star or a black hole. The other component is an intermediate mass star.

Hercules X-1 is composed of a neutron star accreting matter from a normal star (HZ Herculis) probably due to Roche lobe overflow. X-1 is the prototype for the massive X-ray binaries although it falls on the borderline, , between high- and low-mass X-ray binaries.

In July 2020, astronomers reported the observation of a "hard tidal disruption event candidate" associated with ASASSN-20hx, located near the nucleus of galaxy NGC 6297, and noted that the observation represented one of the "very few tidal disruption events with hard powerlaw X-ray spectra".

Celestial X-ray sources

The celestial sphere has been divided into 88 constellations. The International Astronomical Union (IAU) constellations are areas of the sky. Each of these contains remarkable X-ray sources. Some of them have been identified from astrophysical modeling to be galaxies or black holes at the centers of galaxies. Some are pulsars. As with sources already successfully modeled by X-ray astrophysics, striving to understand the generation of X-rays by the apparent source helps to understand the Sun, the universe as a whole, and how these affect us on Earth. Constellations are an astronomical device for handling observation and precision independent of current physical theory or interpretation. Astronomy has been around for a long time. Physical theory changes with time. With respect to celestial X-ray sources, X-ray astrophysics tends to focus on the physical reason for X-ray brightness, whereas X-ray astronomy tends to focus on their classification, order of discovery, variability, resolvability, and their relationship with nearby sources in other constellations.

Within the constellations Orion and Eridanus and stretching across them is a soft X-ray "hot spot" known as the Orion-Eridanus Superbubble, the Eridanus Soft X-ray Enhancement, or simply the Eridanus Bubble, a 25° area of interlocking arcs of Hα emitting filaments. Soft X-rays are emitted by hot gas (T ~ 2–3 MK) in the interior of the superbubble. This bright object forms the background for the "shadow" of a filament of gas and dust. The filament is shown by the overlaid contours, which represent 100 micrometre emission from dust at a temperature of about 30 K as measured by IRAS. Here the filament absorbs soft X-rays between 100 and 300 eV, indicating that the hot gas is located behind the filament. This filament may be part of a shell of neutral gas that surrounds the hot bubble. Its interior is energized by ultraviolet (UV) light and stellar winds from hot stars in the Orion OB1 association. These stars energize a superbubble about 1200 lys across which is observed in the visual (Hα) and X-ray portions of the spectrum.

Proposed (future) X-ray observatory satellites

There are several projects that are proposed for X-ray observatory satellites. See main article link above.

Explorational X-ray astronomy

Usually observational astronomy is considered to occur on Earth's surface (or beneath it in neutrino astronomy). The idea of limiting observation to Earth includes orbiting the Earth. As soon as the observer leaves the cozy confines of Earth, the observer becomes a deep space explorer. Except for Explorer 1 and Explorer 3 and the earlier satellites in the series, usually if a probe is going to be a deep space explorer it leaves the Earth or an orbit around the Earth.

For a satellite or space probe to qualify as a deep space X-ray astronomer/explorer or "astronobot"/explorer, all it needs to carry aboard is an XRT or X-ray detector and leave Earth's orbit.

Ulysses was launched October 6, 1990, and reached Jupiter for its "gravitational slingshot" in February 1992. It passed the south solar pole in June 1994 and crossed the ecliptic equator in February 1995. The solar X-ray and cosmic gamma-ray burst experiment (GRB) had 3 main objectives: study and monitor solar flares, detect and localize cosmic gamma-ray bursts, and in-situ detection of Jovian aurorae. Ulysses was the first satellite carrying a gamma burst detector which went outside the orbit of Mars. The hard X-ray detectors operated in the range 15–150 keV. The detectors consisted of 23-mm thick × 51-mm diameter CsI(Tl) crystals mounted via plastic light tubes to photomultipliers. The hard detector changed its operating mode depending on (1) measured count rate, (2) ground command, or (3) change in spacecraft telemetry mode. The trigger level was generally set for 8-sigma above background and the sensitivity is 10−6 erg/cm2 (1 nJ/m2). When a burst trigger is recorded, the instrument switches to record high resolution data, recording it to a 32-kbit memory for a slow telemetry read out. Burst data consist of either 16 s of 8-ms resolution count rates or 64 s of 32-ms count rates from the sum of the 2 detectors. There were also 16 channel energy spectra from the sum of the 2 detectors (taken either in 1, 2, 4, 16, or 32 second integrations). During 'wait' mode, the data were taken either in 0.25 or 0.5 s integrations and 4 energy channels (with shortest integration time being 8 s). Again, the outputs of the 2 detectors were summed.

The Ulysses soft X-ray detectors consisted of 2.5-mm thick × 0.5 cm2 area Si surface barrier detectors. A 100 mg/cm2 beryllium foil front window rejected the low energy X-rays and defined a conical FOV of 75° (half-angle). These detectors were passively cooled and operate in the temperature range −35 to −55 °C. This detector had 6 energy channels, covering the range 5–20 keV.

Theoretical X-ray astronomy
Theoretical X-ray astronomy is a branch of theoretical astronomy that deals with the theoretical astrophysics and theoretical astrochemistry of X-ray generation, emission, and detection as applied to astronomical objects.

Like theoretical astrophysics, theoretical X-ray astronomy uses a wide variety of tools which include analytical models to approximate the behavior of a possible X-ray source and computational numerical simulations to approximate the observational data. Once potential observational consequences are available they can be compared with experimental observations. Observers can look for data that refutes a model or helps in choosing between several alternate or conflicting models.

Theorists also try to generate or modify models to take into account new data. In the case of an inconsistency, the general tendency is to try to make minimal modifications to the model to fit the data. In some cases, a large amount of inconsistent data over time may lead to total abandonment of a model.

Most of the topics in astrophysics, astrochemistry, astrometry, and other fields that are branches of astronomy studied by theoreticians involve X-rays and X-ray sources. Many of the beginnings for a theory can be found in an Earth-based laboratory where an X-ray source is built and studied.

Dynamos

Dynamo theory describes the process through which a rotating, convecting, and electrically conducting fluid acts to maintain a magnetic field. This theory is used to explain the presence of anomalously long-lived magnetic fields in astrophysical bodies. If some of the stellar magnetic fields are really induced by dynamos, then field strength might be associated with rotation rate.

Astronomical models

From the observed X-ray spectrum, combined with spectral emission results for other wavelength ranges, an astronomical model addressing the likely source of X-ray emission can be constructed. For example, with Scorpius X-1 the X-ray spectrum steeply drops off as X-ray energy increases up to 20 keV, which is likely for a thermal-plasma mechanism. In addition, there is no radio emission, and the visible continuum is roughly what would be expected from a hot plasma fitting the observed X-ray flux. The plasma could be a coronal cloud of a central object or a transient plasma, where the energy source is unknown, but could be related to the idea of a close binary.

In the Crab Nebula X-ray spectrum there are three features that differ greatly from Scorpius X-1: its spectrum is much harder, its source diameter is in light-years (ly)s, not astronomical units (AU), and its radio and optical synchrotron emission are strong. Its overall X-ray luminosity rivals the optical emission and could be that of a nonthermal plasma. However, the Crab Nebula appears as an X-ray source that is a central freely expanding ball of dilute plasma, where the energy content is 100 times the total energy content of the large visible and radio portion, obtained from the unknown source.

The "Dividing Line" as giant stars evolve to become red giants also coincides with the Wind and Coronal Dividing Lines. To explain the drop in X-ray emission across these dividing lines, a number of models have been proposed:
 low transition region densities, leading to low emission in coronae,
 high-density wind extinction of coronal emission,
 only cool coronal loops become stable,
 changes in a magnetic field structure to that an open topology, leading to a decrease of magnetically confined plasma, or
 changes in the magnetic dynamo character, leading to the disappearance of stellar fields leaving only small-scale, turbulence-generated fields among red giants.

Analytical X-ray astronomy
High-mass X-ray binaries (HMXBs) are composed of OB supergiant companion stars and compact objects, usually neutron stars (NS) or black holes (BH). Supergiant X-ray binaries (SGXBs) are HMXBs in which the compact objects orbit massive companions with orbital periods of a few days (3–15 d), and in circular (or slightly eccentric) orbits. SGXBs show typical the hard X-ray spectra of accreting pulsars and most show strong absorption as obscured HMXBs. X-ray luminosity (Lx) increases up to 1036 erg·s−1 (1029 watts).

The mechanism triggering the different temporal behavior observed between the classical SGXBs and the recently discovered supergiant fast X-ray transients (SFXT)s is still debated.

Stellar X-ray astronomy
Stellar X-ray astronomy is said to have started on April 5, 1974, with the detection of X-rays from Capella. A rocket flight on that date briefly calibrated its attitude control system when a star sensor pointed the payload axis at Capella (α Aur). During this period, X-rays in the range 0.2–1.6 keV were detected by an X-ray reflector system co-aligned with the star sensor. The X-ray luminosity of Lx = 1031 erg·s−1 (1024 W) is four orders of magnitude above the Sun's X-ray luminosity.

Stellar coronae
Coronal stars, or stars within a coronal cloud, are ubiquitous among the stars in the cool half of the Hertzsprung-Russell diagram. Experiments with instruments aboard Skylab and Copernicus have been used to search for soft X-ray emission in the energy range ~0.14–0.284 keV from stellar coronae. The experiments aboard ANS succeeded in finding X-ray signals from Capella and Sirius (α CMa). X-ray emission from an enhanced solar-like corona was proposed for the first time. The high temperature of Capella's corona as obtained from the first coronal X-ray spectrum of Capella using HEAO 1 required magnetic confinement unless it was a free-flowing coronal wind.

In 1977 Proxima Centauri is discovered to be emitting high-energy radiation in the XUV. In 1978, α Cen was identified as a low-activity coronal source. With the operation of the Einstein observatory, X-ray emission was recognized as a characteristic feature common to a wide range of stars covering essentially the whole Hertzsprung-Russell diagram. The Einstein initial survey led to significant insights:
X-ray sources abound among all types of stars, across the Hertzsprung-Russell diagram and across most stages of evolution,
the X-ray luminosities and their distribution along the main sequence were not in agreement with the long-favored acoustic heating theories, but were now interpreted as the effect of magnetic coronal heating, and
stars that are otherwise similar reveal large differences in their X-ray output if their rotation period is different.

To fit the medium-resolution spectrum of UX Arietis, subsolar abundances were required.

Stellar X-ray astronomy is contributing toward a deeper understanding of
magnetic fields in magnetohydrodynamic dynamos,
the release of energy in tenuous astrophysical plasmas through various plasma-physical processes, and
the interactions of high-energy radiation with the stellar environment.

Current wisdom has it that the massive coronal main sequence stars are late-A or early F stars, a conjecture that is supported both by observation and by theory.

Young, low-mass stars

Newly formed stars are known as pre-main-sequence stars during the stage of stellar evolution before they reach the main-sequence. Stars in this stage (ages <10 million years) produce X-rays in their stellar coronae. However, their X-ray emission is 103 to 105 times stronger than for main-sequence stars of similar masses.

X-ray emission for pre–main-sequence stars was discovered by the Einstein Observatory. This X-ray emission is primarily produced by magnetic reconnection flares in the stellar coronae, with many small flares contributing to the "quiescent" X-ray emission from these stars. Pre–main sequence stars have large convection zones, which in turn drive strong dynamos, producing strong surface magnetic fields. This leads to the high X-ray emission from these stars, which lie in the saturated X-ray regime, unlike main-sequence stars that show rotational modulation of X-ray emission. Other sources of X-ray emission include accretion hotspots and collimated outflows.

X-ray emission as an indicator of stellar youth is important for studies of star-forming regions. Most star-forming regions in the Milky Way Galaxy are projected on Galactic-Plane fields with numerous unrelated field stars. It is often impossible to distinguish members of a young stellar cluster from field-star contaminants using optical and infrared images alone. X-ray emission can easily penetrate moderate absorption from molecular clouds, and can be used to identify candidate cluster members.

Unstable winds
Given the lack of a significant outer convection zone, theory predicts the absence of a magnetic dynamo in earlier A stars. In early stars of spectral type O and B, shocks developing in unstable winds are the likely source of X-rays.

Coolest M dwarfs
Beyond spectral type M5, the classical αω dynamo can no longer operate as the internal structure of dwarf stars changes significantly: they become fully convective. As a distributed (or α2) dynamo may become relevant, both the magnetic flux on the surface and the topology of the magnetic fields in the corona should systematically change across this transition, perhaps resulting in some discontinuities in the X-ray characteristics around spectral class dM5. However, observations do not seem to support this picture: long-time lowest-mass X-ray detection, VB 8 (M7e V), has shown steady emission at levels of X-ray luminosity (LX) ≈ 1026 erg·s−1 (1019 W) and flares up to an order of magnitude higher. Comparison with other late M dwarfs shows a rather continuous trend.

Strong X-ray emission from Herbig Ae/Be stars

Herbig Ae/Be stars are pre-main sequence stars. As to their X-ray emission properties, some are
 reminiscent of hot stars,
 others point to coronal activity as in cool stars, in particular the presence of flares and very high temperatures.

The nature of these strong emissions has remained controversial with models including
 unstable stellar winds,
 colliding winds,
 magnetic coronae,
 disk coronae,
 wind-fed magnetospheres,
 accretion shocks,
 the operation of a shear dynamo,
 the presence of unknown late-type companions.

K giants
The FK Com stars are giants of spectral type K with an unusually rapid rotation and signs of extreme activity. Their X-ray coronae are among the most luminous (LX ≥ 1032 erg·s−1 or 1025 W) and the hottest known with dominant temperatures up to 40 MK. However, the current popular hypothesis involves a merger of a close binary system in which the orbital angular momentum of the companion is transferred to the primary.

Pollux is the brightest star in the constellation Gemini, despite its Beta designation, and the 17th brightest in the sky. Pollux is a giant orange K star that makes an interesting color contrast with its white "twin", Castor. Evidence has been found for a hot, outer, magnetically supported corona around Pollux, and the star is known to be an X-ray emitter.

Eta Carinae

New X-ray observations by the Chandra X-ray Observatory show three distinct structures: an outer, horseshoe-shaped ring about 2 light years in diameter, a hot inner core about 3 light-months in diameter, and a hot central source less than 1 light-month in diameter which may contain the superstar that drives the whole show. The outer ring provides evidence of another large explosion that occurred over 1,000 years ago. These three structures around Eta Carinae are thought to represent shock waves produced by matter rushing away from the superstar at supersonic speeds. The temperature of the shock-heated gas ranges from 60 MK in the central regions to 3 MK on the horseshoe-shaped outer structure. "The Chandra image contains some puzzles for existing ideas of how a star can produce such hot and intense X-rays," says Prof. Kris Davidson of the University of Minnesota. Davidson is principal investigator for the Eta Carina observations by the Hubble Space Telescope. "In the most popular theory, X-rays are made by colliding gas streams from two stars so close together that they'd look like a point source to us. But what happens to gas streams that escape to farther distances? The extended hot stuff in the middle of the new image gives demanding new conditions for any theory to meet."

Amateur X-ray astronomy

Collectively, amateur astronomers observe a variety of celestial objects and phenomena sometimes with equipment that they build themselves. The United States Air Force Academy (USAFA) is the home of the US's only undergraduate satellite program, and has and continues to develop the FalconLaunch sounding rockets. In addition to any direct amateur efforts to put X-ray astronomy payloads into space, there are opportunities that allow student-developed experimental payloads to be put on board commercial sounding rockets as a free-of-charge ride.

There are major limitations to amateurs observing and reporting experiments in X-ray astronomy: the cost of building an amateur rocket or balloon to place a detector high enough and the cost of appropriate parts to build a suitable X-ray detector.

History of X-ray astronomy

In 1927, E.O. Hulburt of the US Naval Research Laboratory and associates Gregory Breit and Merle A. Tuve of the Carnegie Institution of Washington explored the possibility of equipping Robert H. Goddard's rockets to explore the upper atmosphere. "Two years later, he proposed an experimental program in which a rocket might be instrumented to explore the upper atmosphere, including detection of ultraviolet radiation and X-rays at high altitudes".

In the late 1930s, the presence of a very hot, tenuous gas surrounding the Sun was inferred indirectly from optical coronal lines of highly ionized species. The Sun has been known to be surrounded by a hot tenuous corona. In the mid-1940s radio observations revealed a radio corona around the Sun.

The beginning of the search for X-ray sources from above the Earth's atmosphere was on August 5, 1948 12:07 GMT. A US Army (formerly German) V-2 rocket as part of Project Hermes was launched from White Sands Proving Grounds. The first solar X-rays were recorded by T. Burnight.

Through the 1960s, 70s, 80s, and 90s, the sensitivity of detectors increased greatly during the 60 years of X-ray astronomy. In addition, the ability to focus X-rays has developed enormously—allowing the production of high-quality images of many fascinating celestial objects.

Major questions in X-ray astronomy
As X-ray astronomy uses a major spectral probe to peer into the source, it is a valuable tool in efforts to understand many puzzles.

Stellar magnetic fields
Magnetic fields are ubiquitous among stars, yet we do not understand precisely why, nor have we fully understood the bewildering variety of plasma physical mechanisms that act in stellar environments. Some stars, for example, seem to have magnetic fields, fossil stellar magnetic fields left over from their period of formation, while others seem to generate the field anew frequently.

Extrasolar X-ray source astrometry

With the initial detection of an extrasolar X-ray source, the first question usually asked is "What is the source?" An extensive search is often made in other wavelengths such as visible or radio for possible coincident objects. Many of the verified X-ray locations still do not have readily discernible sources. X-ray astrometry becomes a serious concern that results in ever greater demands for finer angular resolution and spectral radiance.

There are inherent difficulties in making X-ray/optical, X-ray/radio, and X-ray/X-ray identifications based solely on positional coincidents, especially with handicaps in making identifications, such as the large uncertainties in positional determinants made from balloons and rockets, poor source separation in the crowded region toward the galactic center, source variability, and the multiplicity of source nomenclature.

X‐ray source counterparts to stars can be identified by calculating the angular separation between source centroids and the position of the star. The maximum allowable separation is a compromise between a larger value to identify as many real matches as possible and a smaller value to minimize the probability of spurious matches. "An adopted matching criterion of 40" finds nearly all possible X‐ray source matches while keeping the probability of any spurious matches in the sample to 3%."

Solar X-ray astronomy

All of the detected X-ray sources at, around, or near the Sun appear to be associated with processes in the corona, which is its outer atmosphere.

Coronal heating problem
In the area of solar X-ray astronomy, there is the coronal heating problem. The photosphere of the Sun has an effective temperature of 5,570 K yet its corona has an average temperature of 1–2 × 106 K. However, the hottest regions are 8–20 × 106 K. The high temperature of the corona shows that it is heated by something other than direct heat conduction from the photosphere.

It is thought that the energy necessary to heat the corona is provided by turbulent motion in the convection zone below the photosphere, and two main mechanisms have been proposed to explain coronal heating. The first is wave heating, in which sound, gravitational or magnetohydrodynamic waves are produced by turbulence in the convection zone. These waves travel upward and dissipate in the corona, depositing their energy in the ambient gas in the form of heat. The other is magnetic heating, in which magnetic energy is continuously built up by photospheric motion and released through magnetic reconnection in the form of large solar flares and myriad similar but smaller events—nanoflares.

Currently, it is unclear whether waves are an efficient heating mechanism. All waves except Alfvén waves have been found to dissipate or refract before reaching the corona. In addition, Alfvén waves do not easily dissipate in the corona. Current research focus has therefore shifted towards flare heating mechanisms.

Coronal mass ejection
A coronal mass ejection (CME) is an ejected plasma consisting primarily of electrons and protons (in addition to small quantities of heavier elements such as helium, oxygen, and iron), plus the entraining coronal closed magnetic field regions. Evolution of these closed magnetic structures in response to various photospheric motions over different time scales (convection, differential rotation, meridional circulation) somehow leads to the CME. Small-scale energetic signatures such as plasma heating (observed as compact soft X-ray brightening) may be indicative of impending CMEs.

The soft X-ray sigmoid (an S-shaped intensity of soft X-rays) is an observational manifestation of the connection between coronal structure and CME production. "Relating the sigmoids at X-ray (and other) wavelengths to magnetic structures and current systems in the solar atmosphere is the key to understanding their relationship to CMEs."

The first detection of a Coronal mass ejection (CME) as such was made on December 1, 1971, by R. Tousey of the US Naval Research Laboratory using OSO 7. Earlier observations of coronal transients or even phenomena observed visually during solar eclipses are now understood as essentially the same thing.

The largest geomagnetic perturbation, resulting presumably from a "prehistoric" CME, coincided with the first-observed solar flare, in 1859. The flare was observed visually by Richard Christopher Carrington and the geomagnetic storm was observed with the recording magnetograph at Kew Gardens. The same instrument recorded a crotchet, an instantaneous perturbation of the Earth's ionosphere by ionizing soft X-rays. This could not easily be understood at the time because it predated the discovery of X-rays (by Roentgen) and the recognition of the ionosphere (by Kennelly and Heaviside).

Exotic X-ray sources

A microquasar is a smaller cousin of a quasar that is a radio emitting X-ray binary, with an often resolvable pair of radio jets.
LSI+61°303 is a periodic, radio-emitting binary system that is also the gamma-ray source, CG135+01.
Observations are revealing a growing number of recurrent X-ray transients, characterized by short outbursts with very fast rise times (tens of minutes) and typical durations of a few hours that are associated with OB supergiants and hence define a new class of massive X-ray binaries: Supergiant Fast X-ray Transients (SFXTs).
Observations made by Chandra indicate the presence of loops and rings in the hot X-ray emitting gas that surrounds Messier 87. A magnetar is a type of neutron star with an extremely powerful magnetic field, the decay of which powers the emission of copious amounts of high-energy electromagnetic radiation, particularly X-rays and gamma rays.

X-ray dark stars

During the solar cycle, as shown in the sequence of images at right, at times the Sun is almost X-ray dark, almost an X-ray variable. Betelgeuse, on the other hand, appears to be always X-ray dark. Hardly any X-rays are emitted by red giants. There is a rather abrupt onset of X-ray emission around spectral type A7-F0, with a large range of luminosities developing across spectral class F. Altair is spectral type A7V and Vega is A0V. Altair's total X-ray luminosity is at least an order of magnitude larger than the X-ray luminosity for Vega. The outer convection zone of early F stars is expected to be very shallow and absent in A-type dwarfs, yet the acoustic flux from the interior reaches a maximum for late A and early F stars provoking investigations of magnetic activity in A-type stars along three principal lines. Chemically peculiar stars of spectral type Bp or Ap are appreciable magnetic radio sources, most Bp/Ap stars remain undetected, and of those reported early on as producing X-rays only few of them can be identified as probably single stars. X-ray observations offer the possibility to detect (X-ray dark) planets as they eclipse part of the corona of their parent star while in transit. "Such methods are particularly promising for low-mass stars as a Jupiter-like planet could eclipse a rather significant coronal area."

X-ray dark planets and comets
X-ray observations offer the possibility to detect (X-ray dark) planets as they eclipse part of the corona of their parent star while in transit. "Such methods are particularly promising for low-mass stars as a Jupiter-like planet could eclipse a rather significant coronal area."

As X-ray detectors have become more sensitive, they have observed that some planets and other normally X-ray non-luminescent celestial objects under certain conditions emit, fluoresce, or reflect X-rays.

Comet Lulin

NASA's Swift Gamma-Ray Burst Mission satellite was monitoring Comet Lulin as it closed to 63 Gm of Earth. For the first time, astronomers can see simultaneous UV and X-ray images of a comet. "The solar wind—a fast-moving stream of particles from the sun—interacts with the comet's broader cloud of atoms. This causes the solar wind to light up with X-rays, and that's what Swift's XRT sees", said Stefan Immler, of the Goddard Space Flight Center. This interaction, called charge exchange, results in X-rays from most comets when they pass within about three times Earth's distance from the Sun. Because Lulin is so active, its atomic cloud is especially dense. As a result, the X-ray-emitting region extends far sunward of the comet.

See also

 Balloons for X-ray astronomy
 Crab (unit)
 Gamma-ray astronomy
 History of X-ray astronomy
 IRAS 13224-3809
 List of X-ray space telescopes
 Solar X-ray astronomy
 Stellar X-ray astronomy
 Ultraviolet astronomy
 X-ray telescope

References

Sources
The content of this article was adapted and expanded from http://imagine.gsfc.nasa.gov/ (Public Domain)

External links

 How Many Known X-Ray (and Other) Sources Are There?
 Is My Favorite Object an X-ray, Gamma-Ray, or EUV Source?
 X-ray all-sky survey on WIKISKY
 Audio – Cain/Gay (2009) Astronomy Cast – X-Ray Astronomy

Space plasmas
Astronomical imaging
Astronomical X-ray sources
Observational astronomy
Astronomical sub-disciplines

X-ray astronomy


Johanna Wilhelmina Petronella Damman, known under her nickname Jomanda (born May 5, 1948), is a controversial Dutch healing medium who refers to herself as the Lady of the light.

Background
Born Johanna Wilhelmina Petronella Damman in Deventer, Jomanda is a Dutch spiritualist who described herself as being "a healing medium." She claims to have psychic powers of clairvoyance, empathy and prescience, aided by her late father and other powers from the "world divine". She is known to be a devoted fan of paranormal author Jozef Rulof.

Career
In 1991, she gained national fame after making an appearance on a popular talk show. In the next decade, she held public gatherings in Tiel where she announced that she would be performing healings, which drew large groups of people. During these sessions she would 'infuse' bottles of tap water, which she claimed would make them gain healing properties. She also appeared on radio shows, where people were asked to put a bottle of water in front of their radio in order to have it remotely 'infused'.

Controversy
In 2001 Jomanda gave medical and spiritual advice to the popular Dutch actress Sylvia Millecam, who later died of cancer. In 2004 the Dutch Health Inspectorate filed suit against Jomanda claiming that she and three alternative therapists misled Millecam by claiming that the actress was merely suffering from an inflammation. In October 2006, the investigation was dropped, but in April 2008 an Amsterdam court ruled that Jomanda and two doctors who practise alternative therapies should be prosecuted for their roles in Millecam's death.
The trial started at 30 October 2008. On 12 May 2009 Ronald ter Heegde, Jomanda's former assistant, admitted on television in the Dutch newsmagazine Nova that Jomanda had used other persons to gather information about Sylvia Millecam. She then told Millecam she had gathered this information as a medium. On 12 June 2009 the court found Jomanda not guilty as a party to Millecam's death. The court criticised her actions, but stated that she could not be held fully responsible for Millecam's fate.

The Dutch Federation Against Quacks (Nederlandse Vereniging tegen de Kwakzalverij) listed Jomanda as #15 on their top 20 list of quacks.

In October 2004 Jomanda drew publicity again by stating, in accordance with the ideas of Jozef Rulof, 'Cremation hurts'.

See also

Arthur Ford
Char Margolis
Clever Hans
Cold reading
Forer effect
Hot reading
James Pike
John Edward
Jozef Rulof
Mirin Dajo
Peter Hurkos
Peter Popoff
Uri Geller

References

External links

King Solomon Seals

1948 births
Living people
Dutch psychics
New Age spiritual leaders
People acquitted of manslaughter
People from Deventer
People from Tiel
Spiritualists
Supernatural healing

Jomanda


Piri Reis (full name Hadji Muhiddin Piri Ibn Hadji Mehmed) (about 1465 – 1554 or 1555) was an Ottoman-Turkish admiral and cartographer born between 1465 and 1470 in Gallipoli on the Aegean coast of Turkey. Today, people remember him because of the maps he made. He made the first Ottoman map to show parts of the Americas, the Piri Reis map, in 1513. He drew a second map in 1528. Only a fragment of that map survives today. That fragment however, shows parts of North America, including Greenland. It goes from the coast of Labrador and Newfoundland in the north, to Florida,Cuba and parts of Central America in the south. Therefore, some people believe he drew a map of the Arctic about 200 years before it was discovered.

1460s births
1554 deaths
Admirals
Cartographers
Asian explorers
Turkish military people

Piri Reis


Hebrew names are names that have come from the Hebrew language. Traditionally they come from the Hebrew Bible.

They are mostly used by people living in Jewish or Christian parts of the world, but some are also adapted to the Islamic world, particularly if a Hebrew name is mentioned in the Qur'an.

When Hebrew-speaking Muslims give names, they do not necessarily use Jewish or Christian names. A typical Hebrew name can have many different forms – an important principle of the Jewish religion worldwide is to give a Hebrew name to a child that is used throughout his or her lifetime.

Not all Hebrew names are strictly Hebrew in origin: some may have been "taken" from other languages since ancient times. These include Egyptian, Aramaic, Phoenician, Greek, Latin, Arabic, Spanish, German, and English.

Related pages
Given name

Other websites
Rabbi Shraga Simmonsprint article, 163 Hebrew & Jewish Names for Boys (And Meanings), aish.com

Judaism
Names
Hebrew language

Hebrew name


STS-67 was a human spaceflight mission using  that launched from Kennedy Space Center, Florida on March 2, 1995.

Crew

Mission highlights

Ultraviolet Imaging Experiments

Astro-2 was the second dedicated Spacelab mission to conduct astronomical observations in the ultraviolet spectral regions (the first was the Astro-1 mission flown on STS-35).  The Astro-2 Spacelab consisted of three unique instruments – the Hopkins Ultraviolet Telescope (HUT), the Ultraviolet Imaging Telescope (UIT) and the Wisconsin Ultraviolet Photo-Polarimeter Experiment (WUPPE). These took measurements from objects within the Solar System as well as individual stars, nebulae, supernova remnants, galaxies and active extragalactic objects. The data supplemented the data obtained from the Astro-1 mission.

The purpose of the UIT was to observe UV radiation from space (most UV radiation is absorbed by Earth's atmosphere and cannot be studied from the ground). The data collected from UIT Astro-1 mission provided the first accurate knowledge of UV data from the universe. The UIT in the Astro-2 Spacelab was capable of capturing almost twice the UV spectrum of its predecessor. As STS-67 launched at a different time of year from STS-35, data was collected from portions of the sky that Astro-1 was not able to view.

Middeck Active Control Experiment (MACE)

On the Middeck, science experiments included the Protein Crystal Growth Thermal Enclosure System Vapor Diffusion Apparatus-03 experiment (PCG-TES-03), the Protein Crystal Growth Single Thermal Enclosure System-02 (PCG-STES-02), the Shuttle Amateur Radio Experiment-II (SAREX-II), the Middeck Active Control Experiment (MACE), the Commercial Materials Dispersion Apparatus Instrumentation Technology Associates Experiments-03 (CMIX-03) and the Midcourse Space Experiment (MSX).

The Middeck Active Control Experiment (MACE) was a space engineering research payload and activity. It consisted of a rate gyro, reaction wheels, a precision pointing payload, and a scanning and pointing payload that produces motion disturbances. The goal of the experiment was to test a closed loop control system that could compensate for motion disturbances. On orbit, Commander Stephen S. Oswald and Pilot William G. Gregory used MACE to test about 200 different motion disturbance situations over 45 hours of testing during the mission. Information from MACE was to be used to design better control systems that compensate for motion in future spacecraft.

Getaway Special Payloads

Two Get Away Special (GAS) payloads were also on board. They were the G-387 and G-388 canisters. This experiment was sponsored by the Australian Space Office and AUSPACE ltd. The objectives were to make ultraviolet observations of deep space or nearby galaxies. These observations were made to study the structure of galactic supernova remnants, the distribution of hot gas in the Magellanic Clouds, the hot galactic halo emission, and emission associated with galactic cooling flows and jets. The two GAS canisters were interconnected with a cable. Canister 1 had a motorized door assembly that exposed a UV telescope to space when opened. UV reflective filters on the telescopes optics determine its UV bandpass. Canister 2 contained two video recorders for data storage and batteries to provide experiment power. It was Space Shuttle Endeavour's longest flight.

Mission insignia
The spiral galaxy, Jupiter, and the four moons (total of six space objects) as well as the seven stars of the insignia symbolize the flight's numerical designation in the Space Transportation System's mission sequence. Endeavour, with ASTRO-2, is speeding by.

See also

 List of human spaceflights
 List of Space Shuttle missions
 Outline of space science
 Space Shuttle
STS-80 (17 day 8 hour Shuttle mission)
STS-78 (16 day 21 hour Shuttle mission)
STS-73 (15 days 21 hours Shuttle mission)

References

External links
 NASA mission summary
 STS-67 Video Highlights
 Ultraviolet Imaging Telescope
 Wisconsin Ultraviolet Photo-Polarimeter Experiment
 Middeck Active Control Experiment
 R. R. Jayroe Collection, The University of Alabama in Huntsville Archives and Special Collections Files of Robert R. Jayroe, mission manager for Astro-2.

Space Shuttle missions
Edwards Air Force Base
Spacecraft launched in 1995
Crewed space observatories
Ultraviolet telescopes

STS-67


A G-string or thong is a narrow piece of cloth or leather, or plastic that passes between the buttocks. It  is attached to a band around the hips. It can be worn as a swimwear or  underwear by both men and women. The difference between a G-string and a thong is that a G-string has less material between the legs. This makes it look like a string. Variants of the thong or G-string include the "V-string" and the "T-string".

Origin of the G-string
The G-string or thong is probably the earliest form of clothing known to mankind. It originated in the warmer climates of sub-Saharan Africa where clothing was first worn almost 75,000 years ago. Many tribal peoples, like some of the Khoisan people of southern Africa, wore thongs for many centuries. These early pieces of clothes were made to fit the male genitalia.

The G-string was first developed for men by primitive peoples. However, in modern days, Western thongs are usually worn by females. They first became popular in South America in the 1970s. In Brazil, it was originally a style of swimsuit that had a rear area that became so narrow, that it would disappear between the buttocks.

The origin of the term "G-string" is not fully known. The term was first written about by Americans in the late 1800s. They described the loincloth of Philippine natives. Others say the term came from the G-string on an instrument. The origin of the word "thong" is from the Old English thwong, which is a flexible leather cord.

In other languages
In Lithuania, the G-string is often called stringai or siaurikės.

In Portugal and Brazil, the G-string is often referred called fio dental. This means "dental floss".

In Italy, the G-string is called perizoma.

In Turkey, the G-string is called ipli külot (ipli means "stringed" and külot means "underpants").

In French, German and Dutch, the G-string is usually called "string", a loanword from English.

In Puerto Rico, a Spanish slang term often used for G-string is gistro. This is most commonly used by Reggaeton artists to refer to the underwear style.

In Argentina and Chile, G-string is widely known as colaless. In those countries, cola means buttocks. Colaless means "buttocks-less".

In the Japanese language and in Cantonese, the G-string is widely known as T-back. This is because of its shape when seen from behind. The word is sometimes confused with "tea bag". The term T-back is also commonly used in the Philippines. However, there are also several usages of the term "T-back" in English as well. These include Children's literature author E.L. Konigsburg's T-backs, T-shirts, Coat and Suit. In other kinds of the Chinese language, the G-string is commonly called dingziku (丁字裤). It means "character pants".

In Czech, Estonian, Finnish, German, Hungarian and Spanish the G-string is often called tanga. In Finnish, the plural stringit, "strings", is used, as they are pants, not a "pant".

In Polish the G-string is usually called stringi, which is a pluralized loanword from English (literally: "strings").

In Australia, only the term G-string is used. Thongs are a type of rubber footwear.

In Hebrew, the G-string is called a hutini, a blend word of the Hebrew word hut (meaning "string") and bikini.

References

Underwear
Bottoms (clothing)

Swimwear

G-string


An ensemble is a group of people who work or perform together. By extension, it can mean a coordinated outfit of clothing, or anything where a group contributes to a coordinated whole.

The term is most used in music. A musical ensemble is a group of people who perform instrumental or vocal music. In classical music, trios or quartets often group together instruments from the same instrument family, such as string ensembles or wind ensembles. The term is also used in jazz, where the instruments typically include wind instruments.

An ensemble usually consists of three or four people with similar skill levels. The word originated in late middle English (as an adverb) meaning "at the same time". It is from French, based on the Latin insimul. The noun dates from the mid 18th century.

References

Musical groups

Ensemble


The Gospel of Mark is a book of the Bible. It is the second book of the New Testament and comes after the Gospel of Matthew even though it may have been written before it. The writer is believed to have been John Mark, a friend of Simon Peter, who was one of the Twelve apostles of Jesus.

The four gospels tell the story of the life of Jesus. The word "gospel" means "good news". The Gospel of Mark moves quickly, and the story shows how much Jesus worked during his short 3-year ministry. Mark's gospel tells many things about Jesus which are also found in the Gospel of Matthew and the Gospel of Luke.  Matthew, Mark and Luke are called "Synoptic gospels" for this reason.

Most scholars date Mark AD 65-75. It is thought to be the first of the gospels to be written.  Mark's gospel may have been written with Gentiles in mind.  It gives the meaning of some of Jesus' words in Greek that would have been known to Jews but not to other people.  Mark's leaves out many details in the other gospels, such as the stories about the birth of Jesus.  He includes many stories of Jesus doing miracles, more than any other Bible writer.

In telling about the arrest of Jesus to be crucified, the book mentions a young man who was almost caught by the guards, but who slipped out of his robe and got away.  Some think this young man was Mark himself, since there is no other reason to include such a small detail.  If it was Mark, means that Mark was a follower of Jesus who probably saw him crucified and come back to life after three days.

The last chapter of Mark has some verses after verse 8 that may not have been part of the original gospel, as they are missing is some early hand written copies of the book.  However, they give further information about what Jesus said after his resurrection. These sayings  are similar to what the other gospels record.

Related pages

 Jesus
 Bible
 Christianity

References

2
New Testament books

Gospel of Mark


Robin is a comic book superhero and Batman's sidekick. The character appears in American comic books published by DC Comics. There are many characters that became Robin, but the first one was Dick Grayson. The first version of Robin was presented in Detective Comics #38 (April 1940). He was created by Bob Kane, Bill Finger and Jerry Robinson. The team of Batman and Robin is also called "the Dynamic Duo" or "the Caped Crusaders". He is a member of the Teen Titans.

Batman characters

Robin (comics)


Malchus () was a 5th-century Byzantine historian of an Arab origin from the city of Philadelphia (nowadays Amman). According to the Suda, Malchus was a Byzantine (i.e. from Constantinople); but Photius states that he was a native of Philadelphia; the ancient Rabbah in the country of Ammonitis, east of the River Jordan. His name makes it probable that he originally came from the Arab people around Philadelphia, as his name is alike the Arab name Malek (مالك) .

Malchus probably followed his profession of rhetorician or sophist at Constantinople. According to Suda, he wrote a history extending from the reign of Constantine I to that of Anastasius I; but the work in seven books, of which Photius has given an account (Bibl. cod. 78), and to which he gives the title , comprehended only the period from the final sickness of the Eastern emperor Leo I (473 or 474), to the death of Julius Nepos, emperor of the West (480). It has been supposed that this was an extract from the work mentioned by Suidas, or a mutilated copy: that it was incomplete is said by Photius himself, who says that the start of the first of the seven books showed that the author had already written some previous parts, and that the close of the seventh book showed his intention of carrying it further, if his life was spared.

Some scholars, among them Valesius, have thought that the history of Malchus began with Leo's sickness, and that he was the continuator of Priscus, whose history is supposed to have left off at that point. Barthold Georg Niebuhr supposed that this coincidence arose from Photius having met with a portion only of the work of Malchus, which had been inserted in some historical Catena after the work of Priscus; or that the history of the previous period had been given by Malchus in another work. Suidas speaks of the history in its whole extent; it may have been published in successive parts, as the author was able to finish it; and Photius possibly had met with only one part.

Photius praises the style of Malchus as a model of historical composition; pure, free from redundancy and consisting of well-selected words and phrases. He notices also his eminence as a rhetorician, and says that he was favourable to Christianity; a statement which has been thought inconsistent with the praises for Pamprepius. The works of Malchus are lost, except the portions contained in the Excerpta of Constantine VII, and some extracts in Suda.

References

Notes

External links
The surviving portions of his works, in Greek and with Latin translations, can be found in the Fragmenta historicorum Graecorum of Karl Wilhelm Ludwig Müller, vol. 4.

5th-century Byzantine historians

Malchus (historian)


In mathematics, the Schwarz–Ahlfors–Pick theorem is an extension of the Schwarz lemma for hyperbolic geometry, such as the Poincaré half-plane model.

The Schwarz–Pick lemma states that every holomorphic function from the unit disk U to itself, or from the upper half-plane H to itself, will not increase the Poincaré distance between points. The unit disk U with the Poincaré metric has negative Gaussian curvature −1. In 1938, Lars Ahlfors generalised the lemma to maps from the unit disk to other negatively curved surfaces:

Theorem (Schwarz–Ahlfors–Pick). Let U be the unit disk with Poincaré metric ; let S be a Riemann surface endowed with a Hermitian metric  whose Gaussian curvature is ≤ −1; let  be a holomorphic function. Then

for all

A generalization of this theorem was proved by Shing-Tung Yau in 1973.

References

Hyperbolic geometry
Riemann surfaces
Theorems in complex analysis
Theorems in differential geometry

Schwarz–Ahlfors–Pick theorem


Area codes in Germany () for telephones have  two to five digits, not counting the first zero. The first or "leading" zero must be dialled when calling from inside Germany and not when calling from outside Germany. The area code is not needed when dialling another telephone in the same area, unless one of the telephones is a mobile phone. Usually shorter area codes are used by larger cities, and longer area codes to smaller towns.

The first digit (after the leading zero) shows the region:
(0)2 are found in the west
(0)3 in the east
(0)4 in the north
(0)5 in the north central part of Germany
(0)6 in the south central part of Germany
(0)7 in the southwest
(0)8 in the south and the
(0)9 in the southeast.

(0)1 are special numbers such as mobile phones (015, 016, 017), shared cost service (0180), televoting numbers (013) and 010 for dial-around services. The OLD codes 0130 for free phone numbers and 0190 for premium-rate numbers are now moved to 0800 and 0900 to meet international standards.

Germany
Germany

Area codes in Germany


Leroy Robertson (December 21, 1896 – July 25, 1971) was an American composer and music educator.

Robertson was born in Fountain Green, Utah.  One of his earliest instructors was Anthony C. Lund. He graduated from the New England Conservatory of Music with a certificate in public school music and diplomas in composition, violin (after studies with Harrison Keller), and piano in 1923, the same year he was awarded the Endicott prize for "Overture in E Minor".  Following his graduation, Robertson taught music at North Cache High School in Richmond, Utah and at Pleasant Grove High School in Pleasant Grove, Utah, where he also supervised music in the Alpine School District.

Robertson was appointed to the music faculty at Brigham Young University in 1925. He soon became professor and chairman of the music department, a position he held until 1948.  In 1930, Robertson studied with Ernest Bloch at the San Francisco Conservatory of Music. He would continue his studies with Bloch in Roveredo Capriasca, Switzerland in 1932, and with Hugo Leichtentritt in Berlin, Germany, in 1933. Robertson received a BA degree and an MA degree from Brigham Young University in June 1933.

Between 1933-1945, Robertson composed several works for piano and organ, as well as strings, including his "Songs from the Shadow", "Fantasia for the Organ", "String Quartet", and "Punch and Judy Overture". It was also during this period that he began work on the "Oratorio from the Book of Mormon". In 1945, Robertson was awarded the Utah Institute of Fine Arts Award for "Rhapsody for  Piano and Orchestra". Robertson won the Reichhold Award of $25,000 for "Trilogy for Orchestra" in 1947, which was premiered by the Detroit Symphony Orchestra with Karl Krueger conducting.  The following year, he was appointed professor and chairman of the music department at the University of Utah, a position he held until 1962.  Robertson's "Concerto for Violin and Orchestra" premiered under Maurice Abravanel during the centennial of the University of Utah in 1950 with Utah Symphony Orchestra's concertmaster Tibor Zelig as soloist.  In 1954, he received his Ph.D. from the University of Southern California.

Robertson was instrumental in the promotion of the Utah Symphony and of classical music in Salt Lake City.

He is best known for his Oratorio from the Book of Mormon, which premiered in 1953. The setting of the Lord's Prayer from that oratorio was recorded by the Mormon Tabernacle Choir and released as a 45 single on the flip side of the Battle Hymn of the Republic, which hit the top 50 charts.

Amongst Robertson's works in the 1948 hymnal of the Church of Jesus Christ of Latter-day Saints was the music for "Up! Arouse Thee, O Beautiful Zion", with words by Emily H. Woodmansee. The 1985 edition of the Church's hymnal includes eight of Robertson's hymns, including "On This Day of Joy and Gladness" (hymn #64, both words and music by Robertson), "Let Earth's Inhabitants Rejoice" (hymn #53), ""Great King of Heaven" (hymn #63), "God of Our Fathers, Known of Old" (hymn #80), "I'm A Pilgrim, I'm A Stranger" (hymn #121), "Upon The Cross Of Calvary" (hymn #184), "We Love Thy House, Oh God" (hymn #247) and "Go Ye Messengers of Glory" (hymn #262).

Selected works

1923 Endicott Overture
1936 Quintet in A Minor for Piano and String Quartet
1940 Prelude, Scherzo and Ricercare for orchestra
1940 String Quartet
1944 Rhapsody for piano and orchestra
1945 Punch and Judy Overture
1947 Trilogy, for orchestra
1948 Violin Concerto
1953 The Book Of Mormon, oratorio
1957 American Serenade, for string quartet
1966 Piano Concerto

also

Cello Concerto
Fantasia for organ
Come, Come, Ye Saints, for chorus
Hatikva, for chorus
From The Crossroads, for chorus
The Lord's Prayer, for chorus
Passacaglia for orchestra

References

External links
 Robertson on Classpedia at Musicweb UK
 Robertson on Musicweb International

1896 births
1971 deaths
20th-century classical composers
American male classical composers
American classical composers
American Latter Day Saint hymnwriters
Brigham Young University faculty
People from Fountain Green, Utah
USC Thornton School of Music alumni
University of Utah alumni
University of Utah faculty
Musicians from Utah
20th-century American composers
Latter Day Saints from Utah
20th-century American male musicians

Leroy Robertson


The Z80 microchip was one of the  most popular CPU microchips for computers in the 1980s. The Z80 was created by the Zilog company in 1976. Zilog made less than 50% of all Z80s. They are made by Sharp (company), Toshiba, NEC and many other manufacturers around the world. As of 2010, it is still manufactured for use in embedded systems.

Other websites
Z80 website

Computer processors
Computer science

Z80


The Science Olympiad is a nationwide event in the United States that tests students' knowledge in science and technology. It started in 1982, and takes place every year.

Science Olympiad consists of twenty three events testing students in middle and high school on different science topics, such as astronomy and chemistry.

Science competitions
Events in the United States
1982 establishments in the United States

Science Olympiad


A concert band is an ensemble for playing the instruments using wind. The main constituents are
woodwind instrument family, brass instrument family and percussion instrument family. Sometimes, the string instrument family such as cello and double bass can be included.

There are several names similar to concert band like wind band, symphonic band, symphonic winds, wind orchestra, wind symphony, wind ensemble, or symphonic wind ensemble. Many people frequently confuse concert band with brass band or marching band. The differences between them come from the orchestration (how the music is written for the different parts).

The songs written for the concert band are much more easy to listen because of its repertoires . The repertoires are not only about the orchestral composition. Light music, jazz, march and popular tunes are also played. Even though people don't have special knowledge about it, anyone can enjoy the concert band music. It is highly acclaimed for both its quality and popularity. As the arrangement of concert band music is completed in the 20th century, its modern and dynamic style appeals general public. Plus, many conductors conduct concert bands attracted by its unique orchestration.

Classification

A concert band can be divided into four groups; Professional bands, Military bands, School bands, and Community bands. Except for the professional bands, others are named for the location where the performers play.

Professional bands
Performers playing in professional bands for pay consider the band performance as their job.  There are many professional bands in the world, such as Tokyo Kosei Wind Orchestra and Dallas Wind Symphony.

Military bands
A concert band in the military are called Military bands. Because the repertoires are dynamic and active, concert bands usually perform in the army. Not only the military bands but also marching bands with brass often used for marching there.
 Air Force Academy Band

School Bands
School bands refer to the groups consisting student players in school. In elementary, middle, high school and university, there are many students playing wind instruments for a concert or event. People included here also can be divided into two groups. Playing them as their hobbies or studying them as their majors.
 In United States- Yale University Concert Band
 In South Korea- Korea University Wind Orchestra

Community Bands
A community band is a community-based ensemble. It is sponsored by a town or city. Some are professional players but the others may not be.
 The Philadelphia Wind Symphony
 Salt Lake Symphonic Winds
 Teheran Valley Wind orchestra(In Korea)

Instrumentation

Woodwind instrument
A wind instrument in which sound is produced by the vibration of reeds in the mouthpiece, as a bassoon, clarinet, oboe, or saxophone, or by the passing of air across the mouthpiece, as a flute.

Brass instrument
A brass instrument is defined as an "aerophone," which means it is an instrument where the musician must blow air into the instrument. The musician produces the tone by buzzing the lips into what is generally a cup-shaped mouthpiece. It doesn't mean that the instrument is necessarily made of brass, since instruments that are made of other metals, wood, horn, or even animal bone are included in the family of brass instruments. Other instruments that are made of brass or metals such as the flute or saxophone are not brass instruments.

Percussion instrument

A percussion instrument is an instrument, such as a drum, xylophone, piano, or marimba, in which sound is produced by one object striking another or by being scraped or shaken.

References
Sung-gown Jang(2008), Wind Orchestra Music-general remarks & instruction, published by Abraham church music Academy.(Seoul,Korea)

Other websites
Wilktone
The free dictionary
Directory of American Community Concert Bands and Wind Ensembles

Musical groups

Concert band


Ezzedine Salim (), also known as Abdelzahra Othman Mohammed (23 March 1943 – 17 May 2004, عبد الزهراء عثمان محمد), was an Iraqi politician, author, educator, Islamist theorist and one of the leading members of the Iraqi Dawaa Movement between 1980 and 2004. He served as the President of the Governing Council of Iraq (45th Prime Minister of Iraq) in 2004.

Author of over 50 books, including history, Islamic events and works on education, he is best known in the Muslim world for his work on what he believed to be the social and political role of Islam, particularly in his book Political Opposition in the experience of Imam Ali(as). His magnum opus, Fatima Bint Muhammad, is a high calibre commentary on the life of Fatima, the daughter of Islamic prophet, Muhammad.

Biography

Born in the city of Basra, Salim began studying religion and politics at a young age. At the age of 19 he joined the Shiite group Islamic Dawa Party, whose members were quickly noticed by the Baath Party as a threat to their power. He left Iraq in his early twenties to go and live in Kuwait.

After a short time in Kuwait, he went to Iran where he began his career as an editor in many newspapers as well as his main job in the SCIRI (Supreme Council for the Islamic Revolution in Iraq). During his stay in Iran, he gained recognition as a Mujtahid (a high-ranking Islamic scholar). He wrote over 100 books covering topics ranging from religion to politics.

Salim headed the Daawa al-Islamiyah ("Invitation to Islam") party, an Islamist party officially being referred to (in 2004) as Daawa Islamic Party. Known as a writer, philosopher, thinker and political activist, he started his political party as a vehicle to coordinate opposition against Saddam Hussein. The party was quickly recognized as a strong anti-Saddam group. It gained many supporters over the years, and became respected not only in Iraq, Iran and the Middle East but throughout the world. Salim survived numerous assassination attempts by Saddam's followers, and deliberately changed his name to avoid being tracked.

In July 2003, Salim was given a position on the Iraqi Governing Council by the U.S.-led Coalition Provisional Authority, where he was serving as a crucial member.  At a "town hall" meeting with press and public on 25 April 2004 he was asked whether Iraq could retain its identity as an Arab nation under a democracy. Ezzedine Salim responded, "Iraq is a member of the Arab League, but all are represented here now, including Turkmen, Kurds and Christians for example. Iraq is full of diversity."

He became president of the Council on 1 May 2004. Ezzedine Salim was to serve as Council President until the formal handover of power to a new government on 30 June. However, he was killed by a suicide car bomb near the Green Zone on 17 May 2004. Jama'at al-Tawhid wal-Jihad claimed responsibility.

References

External links
Official website
Memorial website
Izzedin Salim Politically skilful Shia leader recently appointed president of the Iraqi Governing Council
Izzedin Salim Moderate Shia leader trying to balance religion and politics in Iraq

1943 births
2004 deaths
Assassinated Iraqi politicians
Deaths by car bomb in Iraq
Iraqi Shia Muslims
Iraqi terrorism victims
People from Basra
Terrorism deaths in Iraq
Islamic Dawa Party politicians
2000s assassinated politicians in Asia

Ezzedine Salim


John Rouse (Rous, Russe) (1574 – 3 April 1652) was an English librarian, second librarian of the Bodleian in Oxford, and a friend of John Milton.

Life

He was born in Somerset, matriculated at Oxford in 1591, and graduated B.A. from Balliol College on 31 January 1599. He was elected Fellow of Oriel College in 1600, and received his M.A. 27 March 1604.

On 9 May 1620 he was chosen chief librarian of the Bodleian Library, a post he discharged with great vigour and acumen until his death. At that time he occupied 'Cambye's lodgings', also written 'Camby's', once a part of St. Frideswide's Priory as a medieval tenement. He afterwards sold the property to Pembroke College, as a residence for the master.

Rouse annotated a collection of Robert Burton's books which were given to the Bodleian Library by testamentary disposition on Burton's death, and two of his inscriptions are cited by Alan H.Nelson as supplying independent confirmation that, for this learned bibliographer, William Shakespeare was identified by a contemporary as the author of Burton's copies of two of Shakespeare's narrative poems. The inscriptions read.
 Venus and Adonis by Wm Shakespear Lond. 1602
 The rape of Lucrece by Wm Shakespear Imp{er}fet.

About 1635 Rouse formed a friendship with Milton; Barbara Lewalski considers they met in Horton, where Milton was studying. He asked the poet for a complete copy of his works for the library, and Milton in 1647 sent two volumes to Oxford, the prose pamphlets carefully inscribed in his own hand 'to the most excellent judge of books,' and a smaller volume of poems which was stolen or lost on the way. To this circumstance we owe Milton's mock-heroic ode To John Rouse (dated 23 January 1646-7) inserted in a second copy, preserved at the Bodleian.

In 1645 he refused to lend King Charles the 'Histoire Universelle du Sieur d'Aubigné' because the statutes forbade the removal of such a book. Christopher Arnold, professor of history at Nuremberg, and Lambecius both complimented him. He died on 3 April 1652, and was buried in Oriel College Chapel. Rouse wrote a dedicatory preface to a collection of verses addressed to the Danish proconsul, Johan Cirenberg (Oxford, 1631). He also issued an appendix to the Bodleian Catalogue in 1635. His portrait hangs in the Middle Common Room of Oriel College.

Notes

References

1574 births
1652 deaths
English librarians
Bodley's Librarians
16th-century English educators
17th-century English people
Alumni of Balliol College, Oxford
Fellows of Oriel College, Oxford
People from Northamptonshire
Burials in Oxfordshire

John Rouse (librarian)


William Browell (1759–1831), was a captain in the Royal Navy.

Life
Browell was the son of William Browell, formerly midshipman of the Centurion under Commodore Anson. He entered the Navy in 1771 on board the Merlin sloop, and, after serving on various ships, was moved shortly before the engagement off Ushant into the Victory. On 10 November 1778 he was made lieutenant, and was with Captain Macbride in the Artois at the hard-fought battle on the Dogger Bank, 5 August. 1781. In the armament of 1790 he was for a short time in the Canada, and, on that ship being paid off, was appointed to the Alcide, and in the spring of 1793 to the Leviathan. In the Leviathan he was present at the operations at the Siege of Toulon under Lord Hood. On 25 May 1794 he was officially discharged from the Leviathan on promotion; but as the ship was then with the fleet under Lord Howe, and in daily expectation of a battle, it would appear probable that he continued in her as a volunteer, and was present in the action of 1 June. On 29 November, he was posted into the Princess Augusta yacht.

In June 1795 Lord Hugh Seymour, now a rear-admiral, hoisted his flag in the Sans Pareil, and selected Browell as his flag-captain. He thus had a distinguished share in the Battle of Groix on 23 June 1795, and continued in the Sans Pareil during the next two years, including the critical time of the mutiny at Spithead. The squadron under Lord Hugh's immediate command was, however, cruising when the mutiny broke out, and did not come into port until the ships at Spithead had returned to their obedience. In June the Sans Pareil was one of a squadron under Sir Roger Curtis, sent for a few weeks into the North Sea. On its return to Spithead, and while the ship was refitting, Captain Browell, being on shore at Gosport, was severely crushed by a bale of wool falling from a height. The injury to his back was such that for some time his life was despaired of; and though, after a long illness, he partially recovered, he was never again fit for active service.

In 1805 he was appointed one of the captains of Greenwich Hospital, and in 1809 was advanced to be lieutenant-governor, a position which he held until his death, 22 July 1831.

References

1759 births
1831 deaths
Royal Navy officers
18th-century Royal Navy personnel
19th-century Royal Navy personnel
Royal Navy personnel of the American Revolutionary War
Royal Navy personnel of the French Revolutionary Wars

William Browell


Charna Furman (born 12 December 1941) is a Uruguayan architect noted for her design of a communal women's housing project designed to create affordable housing for single mothers. As a prisoner, confined during the Uruguayan Dictatorship, she has become an advocate for people deprived of their civil liberties and participated in the creation of a film regarding her ordeal.

Early life
Jaie Charna Furman Naidich was born on 12 December 1941, in Montevideo, Uruguay to Jaie Naidich and José Furman. She grew up in her maternal grandparents home and was raised in a traditional Jewish family. Her father's family had fled to Uruguay to escape The Holocaust.  Entering architecture studies at the University of the Republic in 1961, she became involved in the work of the Center of Architecture Students () and the Federation of University Students, attending numerous international conferences. In 1968, she joined the Culture Commission and was also involved in the communist youth movement, before graduating in 1973.

Career
Furman joined the faculty of the university as a research assistant in the Climatology Department in 1968 and worked there until her termination for political activism in 1974 after the 1973 Uruguayan coup d'état. Though inactive in leftist groups since her university days, Furman was considered a leftist because of her previous involvement. She and her husband, who worked as a drafter in a furniture company, opened a small decorating boutique filled with craft items. At the end of October, she and her husband were arrested in the middle of the night, though her children were allowed to leave with her mother. She was imprisoned from October 1975 to February 1980 and routinely tortured the first year for her previous communist involvement. She was also subject to anti-Semitic slurs and refused access to food to meet her dietetic restrictions or Jewish literature. After a year, she was moved to the Punta de Rieles Prison, where she remained until her release. At the time of her imprisonment, Furman was a young mother with two children, Alejandro, who was four years old and Aiala, who was two and a half years old.

In 1985, Furman resumed her post as a research assistant with the responsibility of managing housing projects for targeted groups to alleviate poverty and marginalization. After a group of single mothers began to work with social workers and psychologists in 1989 to express some of the difficulties they found in locating safe housing for their families, Furman began planning a project known as Mujeres Jefas de Familia (Women as Head of Families), or colloquially as MUJEFA. The plan for the project, implemented by the city, involved the renovation of a derelict historic property in the city center, into a communal living space for twelve families, but it took four years before the deed to the property was granted. The women began working to clean the property in 1994 to prepare for the construction, which was completed in May 1997. The large house featured three common courtyards, which were retained for the use of the residents and the remaining large rooms were divided into residential apartments. Furman's project was one of the finalists for the 1995 World Habitat Prize, awarded by the Building and Social Housing Foundation of the United Kingdom and was recognized by other competitions in Argentina and Dubai.

Furman was one of the International Habitat Council's Women's Network, which she joined in 1992 and a founder of the Housing Institute for Women () in 1994. She became president of the IVIM in 1996 and that same year, joined the United Nations Conference on Women's Monitoring Commission on Gender and Poverty. In 1997, Furman began working on several neighborhood improvement projects for the Municipal Commissariat of Montevideo (), the Women's commission of the Federation of Housing Cooperatives () and the IVIM. These included the Cooperatives Covisfran, Covipolo, Entrelunas, Olimar and Piramide, which involved gendered spaces and solutions for working women like childcare, safety and micro-enterprise programs.

In 2001, Furman was appointed by the architecture faculty of the University of the Republic to the Thematic Network of Gender Studies. In addition to her urban planning initiatives, Furman taught graduate courses on housing issues, such as designing for low-income sectors, cooperatives and use of alternative technology and recycling to solve social housing challenges and published books and articles on urban housing solutions. Some of her works included Mujefa ya tiene casa: un proyecto piloto y sus impactos en el Uruguay (MUJEFA has home: a pilot project and its impacts in Uruguay, 1996), Soluciones habitacionales para personas adultas mayores (Housing solutions for older adults, 1997), Políticas de vivienda y hábitat. Las necesidades de las mujeres y de los nuevos arreglos familiares siguen sin ser contemplados (Housing and habitat policies: The needs of women and new family arrangements remain unseen, 2000), and Nuevas ecuaciones sociales. Como responden las políticas habitacionales (New social equations: How housing policies respond, 2007).

Retiring in 2004 from the university, Furman became involved in the commission investigating resistance to the dictatorship and served on various neighborhood councils beginning in 2007. She was one of the participants in the creation of a 2005 documentary, Memorias de Mujeres (Memories of Women), directed by Virginia Martínez, which detailed the experiences of women imprisoned during the dictatorship. To survive, the women formed support groups and lived in a communal style to protect each other from their thoughts of suicide, sexual assault, and violence.

References

Citations

Bibliography

1941 births
Living people
Architects from Montevideo
Uruguayan architects
Jewish women

Charna Furman


Pedobear is an internet meme that gained popularity on 4chan. Pedobear is usually posted as a way to mock users requesting or posting sexualized images of children on 4chan.

Pedobear first appeared on 2channel, a popular bulletin board system in Japan and was originally called Kumā (interjection of Kuma which means bear in Japanese) or Safety Bear.

Pedobear has also been featured as iStockphoto wallpaper and was in the background of a cover of the auto magazine Import Tuner.

On July 3, 2009, Michael R. Barrick, a Canadian artist had created two pictures showing Pedobear together with the mascots of 2010 Winter Olympic and Paralympic Games. Gazeta Olsztyńska, a Polish newspaper mistakenly used one of the pictures for a February 4, 2010 front page story about the Olympics in Vancouver.

Other websites
 Pedobear at KnowYourMeme.com

References

Internet memes

Pedobear


Isolde Ahlgrimm (31 July 1914 in Vienna – 11 October 1995 in Vienna) was an Austrian harpsichordist and fortepianist. In 1975 she was awarded the Austrian Gold Medal.

Musical education
Ahlgrimm pursued her early piano studies from 1922 at the Musikakademie, Vienna (now the University of Music and Performing Arts Vienna), under the instruction of such notable teachers as Viktor Ebenstein (perhaps now best remembered as the piano soloist in Eroica (1949 film)), Emil von Sauer and Franz Schmidt.

Revival of early music
Together with her husband, instrument collector Erich Fiala (1911–78), Ahlgrimm played a central role in the revival of interest in the use of period instruments for the performance of Baroque and Classical music.

Ahlgrimm and Fiala presented their long-running series of Concerte für Kenner und Liebhaber ("Concerts for connoisseurs and amateurs") in Vienna between 1937 and 1956; this involved 74 different programs of music from the 16th to the 20th centuries, much of this repertoire receiving its first modern performance.

Career
She was the first to perform and record virtually the entire output of JS Bach for harpsichord. She performed The Bach Cycle in 12 programs in Vienna, 1949–50 and 1952–53. Before some 600 subscribers at the preconcert lectures for four of the programs in the first Bach Cycle, Ahlgrimm was the first harpsichordist to argue the case for performing Bach's last work, The Art of Fugue, in its original form as a keyboard work, an idea also adopted at that time by her younger colleague, Gustav Leonhardt (born 1928).

She performed the work for the first time in 1952 and recorded it a year later as Volume 9 of her JS Bach series. From 1937, Ahlgrimm was the first fortepianist in Europe to use original Viennese instruments in the performance of the music of W. A. Mozart. In 1951, she presented the entire solo output of Mozart in a series of nine concerts (The Mozart Cycle), on original fortepianos by Michael Rosenberger (1790) and Anton Walter (1787).

She gave the first performance of Bach's The Musical Offering in its original form, (recorded with Nikolaus Harnoncourt in 1955). With Erich Fiala, she prepared the first recordings of the Bach harpsichord concertos using original string instruments of the baroque era (drawn from Fiala's extensive collection), tuned to low pitch (c. A = 417) and strung in gut. The ensemble—led by Rudolf Baumgartner and including Nikolaus and Alice Harnoncourt alongside other leading Viennese musicians—was named the Amati Orchestra, since all of the string instruments they used had been made by either members of the Amati dynasty or their students.

Ahlgrimm was a close friend of the German composer Richard Strauss and performed a 79th birthday concert for him in Vienna's Konzerthaus (Mozart-Saal) in 1943. Strauss composed a concert-ending to a suite of dances from his last opera, Capriccio (1942), arranged by Ahlgrimm for solo harpsichord at Strauss's suggestion. The Capriccio Suite was first performed by Ahlgrimm in 1946 and was later published by Edition Schott.

Ahlgrimm joined the teaching staff of the Vienna Academy (later known as University of Music and Performing Arts, Vienna) in 1945; remaining there until 1958 when she joined the faculty of the Mozarteum University of Salzburg. She left that institution in 1962 to rejoin the faculty at the Vienna Academy where she was appointed reader in 1969 and professor in 1975. She retired from teaching in 1984. She served on the juries of many European harpsichord competitions, including those at Bruges, Rome, Geneva and Leipzig.

In addition to her numerous concerts and recordings, Isolde Ahlgrimm published many articles on various aspects of performance practice. She edited a selection of keyboard exercises and etudes, in part to dispel the notion that such exercises were a 19th century invention. This was published under the title Manuale der Orgel und Cembalo-Technik (Manual of Orgen and Harpsichord Technique, Finger Exercises and Etudes 1571-1760). A Dictionary of ornamentation, left unpublished at her death, has been completed by her colleague and Viennese musicologist, Helga Scholz-Michelitsch.

A biography of Ahlgrimm, Isolde Ahlgrimm, Vienna and the early music revival, by her student, Peter Watchorn, was published by Ashgate Publishing in 2007.

Selected discography
JS Bach: Complete Works for Harpsichord (Philips) (1951–56; released 1952–59):
Volume 1 – Das Wohltemperierte Clavier, Book 1, BWV 846–869
Volume 2 – Six French Suites, BWV 812–817
Volume 3 – Twenty Little Preludes, BWV 924–943
Volume 4 – Six English Suites, BWV 806–811
Volume 5 – Six Partitas, BWV 825–830
Volume 6 – Das Wohltemperierte Clavier, Book 2, BWV 870–893
Volume 7 – Goldberg Variations, BWV 988; Italian Variations, BWV 989
Volume 8 – Sonatas for flute and obbligato harpsichord, BWV 1030–1032
Volume 9 – Die Kunst der Fuge, BWV 1080
Volume 10 – Das Musikalische Opfer, BWV 1079 (w/ Harnoncourt)
Volume 11 – Three sonatas for viola da gamba, BWV 1027–1029 (w/N. Harnoncourt)
Volume 12 – Fifteen Inventions and Fifteen Sinfonias, BWV 772–801
Volume 13 – Fantasias, Preludes and Fugues, BWV 903, 899, 904, 906, 944, 917, 918, 919
Volume 14 – Toccatas, BWV 910–916; Passacaglia, BWV 582; Fugues BWV 575–577
Concertos for One and Two Harpsichords, BWV 1052–1062 (w/ Friederike Bretschneider/Amati Orchestra/Erich Fiala, cond.)
Italian Concerto, BWV 971; French Overture, BWV 831; Four Duets, BWV 802–805; Capriccio in B-flat, BWV 992 (recorded Philips, 1975)
(also: Austrian Harpsichord Music, G. F. Handel: Eight "Great" Suites, 1720: Eterna).

Notes

References

External links
 Peter Watchorn about Isolde Ahlgrimm

 More portraits of Isolde Ahlgrimm

Austrian harpsichordists
Women keyboardists
1914 births
1995 deaths
Musicians from Vienna
Austrian keyboardists
20th-century classical musicians
Academic staff of Mozarteum University Salzburg
Women harpsichordists
University of Music and Performing Arts Vienna alumni
Academic staff of the University of Music and Performing Arts Vienna

Isolde Ahlgrimm


The Most Honourable Order of the Bath is a British order of chivalry. It was founded by George I, on 18 May 1725. The name comes from an old ceremony, first mentioned in 1128. In the ceremony, men participated in a vigil of fasting, prayer, and taking a bath. They did this on the day before they were made a knight. The ceremony was abolished in 1815.

The Order is made up of the Sovereign (the British Sovereign), the Great Master (vacant since Charles III became King), and three classes of members: (Highest to lowest)

Knight or Dame Grand Cross (GCB)
Knight or Dame Commander (KCB or DCB)
Companion (CB)

Originally founded as a military order of chivalry, the star (or pip) is worn as army officers' rank insignia. The insignia is that of the Order of the Bath. Members of the order now belong to either the Civil or the Military Division. The Order's motto is Tria juncta in uno (Latin for "Three joined in one"). This is a reference to either the union of England, Scotland and Ireland, or to the Holy Trinity. A symbol of the Order that is seen over and over has three crowns in it. Another motto, Ich dien (German for "I serve") is used occasionally, but only by members of the Order who serve in the military.

The Order is the fourth oldest of the British Orders of Chivalry, after The Most Noble Order of the Garter, The Most Ancient and Most Noble Order of the Thistle, and The Most Illustrious Order of St Patrick. The last of those Orders–which relates to Ireland, no longer a part of the United Kingdom–still exists, but is no longer active; no appointments have been made to it since 1934.

18th-century establishments in Great Britain

Order of the Bath


A multileaf collimator (MLC) is a Collimator or beam-limiting device that is made of individual "leaves" of a high atomic numbered material, usually tungsten, that can move independently in and out of the path of a radiotherapy beam in order to shape it and vary its intensity.

MLCs are used in external beam radiotherapy to provide conformal shaping of beams. Specifically, conformal radiotherapy and Intensity Modulated Radiation Therapy (IMRT) can be delivered using MLCs.

The MLC has improved rapidly since its inception and the first use of leaves to shape structures in 1965  to modern day operation and use. MLCs are now widely used and have become an integral part of any radiotherapy department. MLCs were primarily used for conformal radiotherapy, and have allowed the cost-effective implementation of conformal treatment with significant time saving, and also have been adapted for use for IMRT treatments. For conformal radiotherapy the MLC allows conformal shaping of the beam to match the borders of the target tumour. For intensity modulated treatments the leaves of a MLC can be moved across the field to create IMRT distributions (MLCs really provide a fluence modulation rather than intensity modulation).

The MLC is an important tool for radiation therapy dose delivery. It was originally used as a surrogate for alloy block field shaping and is now widely used for IMRT. As with any tool used in radiotherapy the MLC must undergo commissioning and quality assurance. Additional commissioning measurements are completed to model a MLC for treatment planning. Various MLCs are provided by different vendors and they all have unique design features as determined by specifications of design, and these differences are quite significant.

References

Medical equipment
Medical physics
Particle accelerators
Radiation therapy

Multileaf collimator


was a Japanese musician, famous for his  koto playing.

He was born in Kobe. He lost his sight in 1902, when he was 8 years old, and started his study in koto under the guidance of Nakajima Kengyo II, dedicating the rest of his life to the instrument. In 1907 he moved with his family to Incheon, in southern Korea. When he was 14 years old, in 1909 he finished his first composition, Mizu no Hentai. At 18 he reached the rank of kengyo, the highest rank for a koto performer.

Miyagi moved to Tokyo in 1917, and in 1919 he did his first recital of his own compositions. In 1920, he took part in the Great Recital of the New Japanese Music with Seifu Yoshida and Nagayo Motoori. He was reckoned as an authority in the new Japanese music, achieving notability in the early Shōwa period. In 1925 he participated in one of the first radio presentations in Japan, and in 1929 he signed an exclusive contract with Victor Record Company, current JVC. He composed his most famous piece, Haru no Umi (The Sea in Spring), in 1929.

In 1930 he became a lecturer at the Tokyo College of Music (current Tokyo University of the Arts), until he was appointed professor in 1937. In 1932 French violinist Renée Chemet visited Japan on a concert tour. After hearing Miyagi perform Haru no Umi Chemet arranged the shakuhachi part for violin, which she and Miyagi then recorded for distribution in Japan and Europe. He gained worldwide notability after the issuing of his albums in Japan, United States and UK.

After the Second World War, in 1948, he was appointed to the Academy of Arts of Japan. On 25 June 1956 he died after falling from a train in Kariya, Aichi during one of his tours. He wrote more than 500 pieces, improved Japanese string instruments, and invented new kotos with 17 strings (bass koto) and 80 strings. He was also an essayist, and published more than ten books including Ame no Nenbutsu.

Michio Miyagi Memorial Hall
The Michio Miyagi Memorial Hall, Shinjuku City, Tokyo, was opened in 1978 on the site where he spent his last years. The museum includes his personal instruments and artifacts, the library where he composed his music and wrote his essays, a room with his music and videos, a library, lecture hall and music hall for concerts.

References
Prescott, Anne, Miyagi Michio, the father of modern Koto music his life, works and innovations, and the environment which enabled his reforms, Dissertation, Kent State University, 1997.
Chiba Junnosuke, Oto ni Ikiru; Miyagi Michio Den, Tokyo: Kodansha, 1992.

External links

Miyagi Koto Association Website (Accessed 15-10-2017)
Michio Miyagi Memorial Hall (Accessed 15-10-2017)

1894 births
1956 deaths
20th-century classical composers
20th-century Japanese composers
20th-century Japanese male musicians
Blind classical musicians
Blind scholars and academics
Japanese blind people
Japanese classical composers
Japanese male classical composers
Japanese musical instrument makers
Musicians from Kobe
So players
Railway accident deaths in Japan
Accidental deaths from falls

Michio Miyagi