IRAS

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IRAS

The Infrared Astronomical Satellite (IRAS) was the first-ever space-based observatory

Observatory

An observatory is a location used for observing terrestrial and/or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed....
to perform a survey of the entire sky

Sky

The sky is the part of the atmosphere or of outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons....
at infrared

Infrared

Infrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light , but shorter than that of terahertz radiation and microwaves ....
wavelength

Wavelength

In physics, wavelength is the distance between repeating units of a propagating wave of a given frequency. It is commonly designated by the Greek language letter lambda ....
s.

Launched on January 25, 1983, its mission lasted ten months. The telescope was a joint project of the United States

United States

The United States of America is a Federal government constitutional republic comprising U.S. state and a federal district. The country is situated mostly in central North America, where its Contiguous United States and Washington, D.C., the Capital districts and territories, lie between the Pacific Ocean and Atlantic Oceans, Borders of the U...
(NASA

NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
), the Netherlands

Netherlands

The Netherlands is a country that is part of the Kingdom of the Netherlands. It is a parliamentary democratic constitutional monarchy. The Netherlands is located in North-West Europe, and bordered by the North Sea to the north and west, Belgium to the south, and Germany to the east....
(NIVR

Netherlands Agency for Aerospace Programmes

The Netherlands Agency for Aerospace Programmes is the official space exploration agency of the Netherlands.See also, ESA....
), and the United Kingdom

United Kingdom

The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom , the UK or Britain,is a sovereign state located off the northwestern coast of continental Europe....
(SERC

Science and Engineering Research Council

The Science and Engineering Research Council used to be the United Kingdom agency in charge of publicly funded scientific and engineering research activities including astronomy, biotechnology and biological sciences, space research and particle physics....
).

was the first observatory to perform an all-sky survey at infrared wavelengths.

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Encyclopedia

The Infrared Astronomical Satellite (IRAS) was the first-ever space-based observatory

Observatory

Sky

The sky is the part of the atmosphere or of outer space visible from the surface of any astronomical object. It is difficult to define precisely for several reasons....
at infrared

Infrared

Infrared radiation is electromagnetic radiation whose wavelength is longer than that of visible light , but shorter than that of terahertz radiation and microwaves ....
wavelength

Wavelength

United States

NASA

The National Aeronautics and Space Administration is an agency of the Federal government of the United States, responsible for the nation's public list of space agencies....
), the Netherlands

Netherlands

Netherlands Agency for Aerospace Programmes

The Netherlands Agency for Aerospace Programmes is the official space exploration agency of the Netherlands.See also, ESA....
), and the United Kingdom

United Kingdom

Science and Engineering Research Council

Mission

IRAS was the first observatory to perform an all-sky survey at infrared wavelengths. It mapped 96% of the sky four times, at 12, 25, 60 and 100 micrometre wavelengths, with resolutions ranging from 30 arcseconds at wavelength 12 micrometers to 2 arcminutes at wavelength 100 micrometers. It discovered about 350,000 sources, many of which are still awaiting identification. About 75,000 of those are believed to be starburst galaxies

Starburst galaxy

A starburst galaxy is a galaxy in the process of an exceptionally high rate of star formation, compared to the usual star formation rate seen in most galaxies....
, still enduring their star

Star

A star is a massive, luminous ball of Plasma that is held together by its own gravity. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth....
-formation stage. Many other sources are normal stars with disks of dust around them, possibly the early stage of a planetary system

Planetary system

A planetary system consists of the various non-stellar objects orbiting a star such as planets, natural satellites, asteroids, meteoroids, comets, and cosmic dust....
formation. New discoveries included a dust disk around Vega

Vega

Vega is the brightest star in the constellation Lyra, the list of brightest stars in the night sky and the second brightest star in the northern Celestial sphere, after Arcturus....
and the first images of the Milky Way Galaxy's

Milky Way

The Milky Way, sometimes called simply the Galaxy, is the galaxy in which the Solar System is located. It is a barred spiral galaxy that is part of the Local Group of galaxies....
core.

IRAS's life, like most of infrared satellites that followed after IRAS, was limited by its cooling system: to effectively work in the infrared domain, the telescope must be cooled to impressively low temperatures. In IRAS' case, 475 liters of superfluid

Superfluid

Superfluidity is a phase or description of heat capacity in which unusual effects are observed when liquids, typically of helium-4 or helium-3, overcome friction by surface interaction when at a stage at which the liquid's viscosity becomes zero....
helium

Helium

Helium is a colorless, odorless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas group in the periodic table and whose atomic number is 2....
kept the telescope at a temperature of 2 kelvin

Kelvin

The kelvin is a Units of measurement of temperature and is one of the seven SI base units. The Kelvin scale is a Thermodynamic temperature scale where absolute zero, the theoretical absence of all thermal energy, is zero ....
s (about −271 °C

Celsius

Celsius is a temperature scale that is named after the Swedish astronomer Anders Celsius , who developed a similar temperature scale two years before his death....
), keeping the satellite cool by evaporation

Evaporation

Evaporation is the slow vaporization of a liquid and the reverse of condensation. A type of phase transition, it is the process by which molecules in a liquid State of matter spontaneously become gaseous ....
. The on-board supply of fluid helium depleted after 10 months on November 22 1983, causing the telescope temperature to rise, preventing further observations.

IRAS was designed to catalogue fixed sources, so it scanned the same region of sky several times. Jack Meadows led a team at Leicester University, including John Davies and Simon Green, which searched the rejected sources for moving objects. This led to the discovery of three asteroid

Asteroid

Asteroids, sometimes called minor planets or planetoids, are small Solar System bodies in orbit around the Sun, smaller than planets but larger than meteoroids....
s, including 3200 Phaethon

3200 Phaethon

3200 Phaethon is an Apollo asteroid and an extinct comet.Simon F. Green and John K. Davies, while searching Infrared Astronomical Satellite data for moving objects, discovered 3200 Phaethon in images from October 11, 1983....
(an Apollo asteroid

Apollo asteroid

The Apollo asteroids are a group of near-Earth asteroids named after 1862 Apollo, the first asteroid of this group to be discovered by Karl Wilhelm Reinmuth....
and the parent body of the Geminid

Geminids

The Geminids are a meteor shower caused by an object named 3200 Phaethon, which is thought to be an extinct comet. The meteors from this shower can be seen in mid-December and usually peak around 12-14 of the month....
meteor shower

Meteor shower

Meteor showers, some of which are known as "meteor storms" , "meteor outbursts,"or "star storm are celestial events in which a number of meteors are observed to radiate from one point in the sky....
), six comets, and a huge dust trail associated with comet Tempel-2. The comets included the periodic comet

Comet

A comet is a Small Solar System body that orbits the Sun and, when close enough to the Sun, exhibits a visible coma or a tail?both primarily from the effects of solar radiation upon the Comet nucleus....
s 126P/IRAS and 161P/Hartley-IRAS

161P/Hartley-IRAS

161P/Hartley-IRAS is a periodic comet in our solar system.External links...
and comet IRAS-Araki-Alcock

Comet IRAS-Araki-Alcock

Comet IRAS-Araki-Alcock is a small comet that, in 1983, made the closest approach to the earth of any comet in 200 years; only Lexell's Comet, in 1770, and 55P/Tempel-Tuttle, in 1366, are thought to have come closer....
(C/1983 H1), which made a close approach to the Earth in 1983.

Several space infrared telescopes have continued and greatly expanded the study of the infrared Universe, such as the Infrared Space Observatory

Infrared Space Observatory

The Infrared Space Observatory was a space telescope for infrared light designed and operated by the European Space Agency , in cooperation with ISAS and National Aeronautics and Space Administration....
launched in 1995, the Spitzer Space Telescope

Spitzer Space Telescope

The Spitzer Space Telescope is an infrared space observatory. It is the fourth and final of NASA's Great Observatories program.The planned nominal mission period was to be 2.5 years with a pre-launch expectation that the mission could extend to five or slightly more years until the onboard liquid helium supply was exhausted....
launched in 2003, and the AKARI

Akari

* AKARI, in astronomy, is an infrared astronomy satellite developed by JAXA, in cooperation with institutes of Europe and Korea.* AKARI Project, in telecommunications, refers to the AKARI Architecture Design Project of Japan....
Space Telescope launched in 2006.

Asteroid
Asteroid

**Asteroids**, sometimes called **minor planets** or **planetoids**, are small Solar System bodies in orbit around the Sun, smaller than planets but larger than meteoroids....
s discovered: 3
3200 Phaethon 3200 Phaethon 3200 Phaethon is an Apollo asteroid and an extinct comet.Simon F. Green and John K. Davies, while searching Infrared Astronomical Satellite data for moving objects, discovered 3200 Phaethon in images from October 11, 1983....	October 11 1983
3728 IRAS 3728 IRAS 3728 IRAS is a small asteroid belt asteroid. It is 9.76 km in diameter. It is one of the three asteroids discovered by the IRAS in 1983, and was named in honour of the satellite....	August 23 1983
(10714) 1983 QG	August 31 1983

Trivia

The observatory also made headlines briefly with the discovery of an "unknown object" that was at first described as "possibly as large as the giant planet Jupiter

Jupiter

Jupiter is the fifth planet from the Sun and the Solar system by size planet within the Solar System. It is two and a half times as massive as all of the other planets in our Solar System combined....
and possibly so close to Earth

Earth

Earth is the third planet from the Sun. Earth is the largest of the terrestrial planets in the Solar System in diameter, mass and density. It is also referred to as the World and Wiktionary:Terra.Note that by International Astronomical Union convention, the term "Terra" is used for naming extensive land masses, rather...
that it would be part of this solar system

Solar System

The Solar System consists of the Sun and those Astronomical object bound to it by gravity: the eight planets and five dwarf planets, their 173 known Natural satellite, and billions of Small Solar System body....
." However, further analysis revealed that, of several unidentified objects, nine were distant galaxies and the tenth was "intergalactic cirrus

Infrared Cirrus

Infrared cirrus are filamentary structures seen in infrared light. The name is given because the structure looks cloud-like in appearance. First detected by the IRAS at wavelengths of 60 and 100 micrometres....
". None were found to be Solar System bodies.