'Swift' action on ray bursts

British astronomers have won approval to build and launch a spacecraft to study mysterious, violent bursts of gamma rays. Last week Nasa selected the spacecraft, called Swift, as one of its key space science missions for the next millennium. It is due for launch in 2003, writes Alison Goddard.

Gamma ray bursts are the most violent events in the universe. The explosions are so vast that they outshine the whole of the rest of the universe. They happen roughly once a day at random points on the sky and can last from a fraction of a second to minutes. Scientists do not know how they are generated; Swift's data will help provide answers.

The Swift spacecraft will be built by researchers at the University of Leicester and the Mullard Space Laboratory, part of University College London, along with scientists from the Goddard Space Flight Center near Washington DC and Pennsylvania State University.