Infrared Astronomical Satellite


Infrared Astronomical Satellite

 U.S.-U.K.-Netherlands satellite launched in 1983 that was the first space observatory to map the entire sky at infrared wavelengths.

      After a series of brief studies by infrared instruments carried on sounding rockets had detected about 4,000 celestial sources of infrared radiation, the United States, the United Kingdom, and The Netherlands built IRAS to map the sky at infrared wavelengths of 12, 25, 60, and 100 micrometres. It was launched on Jan. 25, 1983, on a Delta rocket from Vandenberg Air Force Base in California into a polar orbit at an altitude of 900 km (550 miles).

      Its 60-cm- (24-inch-) diameter telescope was cooled by superfluid helium that chilled the structure down to 10 K (−263 °C, or −442 °F) and the detector to 2 K (−271 °C, or −456 °F). This was necessary because if the telescope were not cooled down, its own thermal radiation at infrared wavelengths would swamp the much fainter radiation from astronomical objects. During each orbit, IRAS scanned a strip of sky 30 arc minutes wide, and successive strips overlapped by 15 arc minutes to ensure that nothing was missed. On its first day of observations (Feb. 10, 1983), it doubled the number of known infrared sources. Its operational life was defined by the rate at which it consumed its coolant, and it had to be shut down on Nov. 21, 1983, by which time it had noted over a quarter of a million sources. Various preliminary data sets were released between 1984 and 1986, and these were then refined several times to produce the final IRAS Sky Survey Atlas, which was published in 1993.

 IRAS proved adept at discovering comets (it is credited as “discoverer” of six of them). It revealed that some young stars have disks of minute, solid dust particles, suggesting that such stars are in the process of forming planetary systems. IRAS also discovered many previously unknown galaxies that emit most of their energy in the infrared portion of the electromagnetic spectrum (these are known as ultraluminous infrared galaxies), apparently owing to a massive burst of star formation during the merger of two galaxies.

David M. Harland
 

* * *


Universalium. 2010.

Look at other dictionaries:

  • Infrared Astronomical Satellite — IRAS (télescope spatial) Pour les articles homonymes, voir IRAS (homonymie). IRAS …   Wikipédia en Français

  • Infrared Astronomical Satellite — Zeichnung von IRAS in der Erdumlaufbahn IRAS im Weltraumsimulator Der …   Deutsch Wikipedia

  • Infrared Astronomy Satellite — IRAS (télescope spatial) Pour les articles homonymes, voir IRAS (homonymie). IRAS …   Wikipédia en Français

  • Astronomical survey — Astronomical surveys generally involve imaging or mapping of regions of the sky using Telescopes. In the past,surveys have been usually restricted to one band of wavelengths of electromagnetic radiation (e.g. light or radio) or to measurements of …   Wikipedia

  • Infrared Space Observatory — ▪ satellite   European Space Agency (ESA) satellite that observed astronomical sources of infrared radiation from 1995 to 1998.       After the spectacular success in 1983 of the short lived Infrared Astronomical Satellite, which produced the… …   Universalium

  • Infrared Space Observatory — Infobox Space Telescope name = Infrared Space Observatory background = caption = organization = European Space Agency (ESA) major contractors = Aerospatiale (currently Thales) alt names = nssdc id = 1995 062A location = In decaying orbit orbit… …   Wikipedia

  • infrared astronomy — the study of infrared radiation emitted by celestial objects. [1960 65] * * * Study of astronomical objects by observing the infrared radiation they emit. Its techniques enable examination of many celestial objects that give off energy at… …   Universalium

  • astronomical observatory —       any structure containing telescopes and auxiliary instruments with which to observe celestial objects. Observatories can be classified on the basis of the part of the electromagnetic spectrum in which they are designed to observe. The… …   Universalium

  • satellite observatory — ▪ astronomy  Earth orbiting spacecraft that allows celestial objects and radiation to be studied from above the atmosphere. Astronomy from Earth s surface is limited to observation in those parts of the electromagnetic spectrum (see… …   Universalium

  • Infrared Processing and Analysis Center — The Infrared Processing and Analysis Center (IPAC) is the NASA science center which is responsible for the data processing, analysis, and archiving for NASA s infrared astronomy and astrophysics missions. It is located on the campus of the… …   Wikipedia


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.