Editing Marshall Space Flight Center (section)

====Compton Gamma Ray Observatory====
The [[Compton Gamma Ray Observatory]] (CGRO) was another of NASA's [[Great Observatories]]. The CGRO was launched April 5, 1991, on Shuttle flight STS-37. At {{cvt|37,000|lb|kg}}, it was the heaviest astrophysical payload ever flown at that time. CGRO was 14 years in development by NASA; TRW was the builder. Gamma radiation is the highest energy-level of electromagnetic radiation, having energies above 100 [[electronvolt|keV]] and frequencies above 10 [[hertz|exahertz]] (10<sup>19</sup> Hz). Gamma radiation is produced by [[atom|sub-atomic]] particle interactions, including those in some astrophysical processes. The continuous flow of cosmic rays bombarding space objects, such as the Moon, generate this radiation. Gamma rays also result in bursts from nuclear reactions. The CGRO was designed to image continuous radiation and to detect bursts.{{citation_needed|date=July 2019}}

MSFC was responsible for the Burst and Transient Source Experiment, (BATSE). This triggered on sudden changes in gamma count-rates lasting 0.1 to 100 s; it was also capable of detecting less impulsive sources by measuring their modulation using the Earth [[occultation]] technique. In nine years of operation, BATSE triggered about 8000 events, of which some 2700 were strong bursts that were analyzed to have come from distant galaxies.{{citation_needed|date=July 2019}}

Unlike the Hubble Space Telescope, the CGRO was not designed for on-orbit repair and refurbishment. Thus, after one of its gyroscopes failed, NASA decided that a controlled crash was preferable to letting the craft come down on its own at random. On June 4, 2000, it was intentionally de-orbited, with the debris that did not burn up falling harmlessly into the Pacific Ocean. At MSFC, [[Gerald J. Fishman]]{{when|date=July 2019}} is the principal investigator of a project to continue examination of data from BATSE and other gamma-ray projects. The 2011 [[Shaw Prize]] was shared by Fishman and Italian [[Enrico Costa (physicist)|Enrico Costa]] for their gamma-ray research.<ref>{{cite news |title=Huntsville NASA scientist shares $1 million Shaw prize for astronomy |date=June 17, 2011 |author=Lee Roop |url=https://www.al.com/breaking/2011/06/huntsville_nasa_scientist_shar.html |website=al.com |access-date=June 6, 2023 |archive-date=June 7, 2023 |archive-url=https://web.archive.org/web/20230607042506/https://www.al.com/breaking/2011/06/huntsville_nasa_scientist_shar.html |url-status=live }}</ref>