Compton Gamma Ray Observatory
former NASA space observatory
The Compton Gamma Ray Observatory (CGRO) was a space observatory detecting photons with energies from 20 keV to 30 GeV, in Earth orbit from 1991 to 2000. The observatory featured four main telescopes in one spacecraft, covering X-rays and gamma rays, including various specialized sub-instruments and detectors. Following 14 years of effort, the observatory was launched from Space Shuttle Atlantis during STS-37 on April 5, 1991, and operated until its deorbit on June 4, 2000. It was deployed in low Earth orbit at 450 km (280 mi) to avoid the Van Allen radiation belt. It was the heaviest astrophysical payload ever flown at that time at 16,300 kilograms (35,900 lb).
Costing $617 million, the CGRO was part of NASA's Great Observatories series, along with the Hubble Space Telescope, the Chandra X-ray Observatory, and the Spitzer Space Telescope. It was the second of the series to be launched into space, following the Hubble Space Telescope. The CGRO was named after Arthur Compton, an American physicist and former chancellor of Washington University in St. Louis who received the Nobel Prize for work involved with gamma-ray physics. CGRO was built by TRW (now Northrop Grumman Aerospace Systems) in Redondo Beach, California.
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The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Sep 4, 2026. The linked authority identifier is Q41519. VIAF identifies the subject as 146858764. The Library of Congress control number is no95029784. 2 of 3 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank. The first chronological checks are 1991 and 2000.
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This entry incorporates text from “Compton Gamma Ray Observatory” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.