An orbiting gamma-ray space observatory to make observations at high energies extending up to about 300 GeV. Led by NASA, it has participation from France, Germany, Japan, Italy, and Sweden. GLAST carries two instruments, the main one being the Large Area Telescope (LAT) which will make gamma-ray images of astronomical objects. The second instrument is the GLAST Burst Monitor (GBM), which looks for gamma-ray bursts. The GBM has a field of view that will enable it to watch over two-thirds of the sky at a time. Fermi was launched in June 2008, and on 12 April 2017 the LAT detected its billionth extraterrestrial gamma ray. On 17 August 2017, just 1.7 seconds after a gravitational wave was detected on Earth, GLAST registered a brief flash of gamma radiation (a gamma-ray burst), which came from a hypernova—an event never before seen by astronomers and the first cosmic event ever detected via both traditional telescopes and gravitational wave detectors.