Gamma-ray bursts are the most luminous explosions in the cosmos. Most of these events occur when the core of a massive star runs out of nuclear fuel, collapses under its own weight, and forms a black hole. The black hole then drives jets of particles that drill all the way through the collapsing star at nearly the speed the light, as shown in this artist's rendering.
On April 27, 2013, a blast of light from a dying star in a distant galaxy became the focus of astronomers around the world. The explosion designated GRB 130427A, tops the charts as one of the brightest ever seen. The Fermi Gamma-ray Burst Monitor captured the initial wave of gamma-rays from GRB 130427A shortly after 3:47 a.m. EDT April 27. In its first three seconds alone, the "monster burst" proved brighter than almost any burst previously observed. The Fermi Large Area Telescope detected gamma-rays from this event for a record-setting 20 hours.