Gamma ray burst 080916C. Composite image of the largest gamma ray burst (GRB) ever observed. This explosion occurred in the constellation Carina, 12.2 billion light years from Earth, on 15th September 2008. GRBs are extremely high-energy events. The burst, a flash of radiation seen as two jets, may be as bright as the rest of the universe combined for a few seconds. They may be the result of a neutron star being torn apart by a black hole. Image taken by the ultraviolet/optical telescope and the X-ray telescope on NASA's Swift Gamma-ray Explorer satellite.