A Gamma-ray burst (GRB) is a flash a gamma rays that are thought to be either the merging of two neutron stars, or the death of a massive star into a black hole. Long gamma-ray bursts, which are those that last over 2 seconds, are thought to be the result of a core-collapse supernova. Short gamma-ray bursts, which are those that last less than 2 seconds, are hypothesized to be the result of a binary neutron stars merging. NASA’s Swift spacecraft was launched on November 20th, 2004. Its mission was to observe 200 gamma ray bursts. It has now seen over 500 of them.
In its first five years in orbit, NASA’s Swift satellite has given astronomers more than they could have hoped for. Its discoveries range from a nearby nascent supernova to a blast so far away that it happened when our universe was only 5 percent of its present age.
Swift primarily studies gamma-ray bursts (GRBs) — the biggest and most mysterious explosions in the cosmos. On April 13, the spacecraft’s “burst-o-meter” cataloged its 500th GRB.
