NASA detects rare gamma ray burst

National Aeronautics and Space Administration scientists have, for the first time, detected and pinned down the location of a short gamma-ray burst, lasting only 50 milliseconds, the agency announced Friday.

The burst marks the birth of a black hole and the astronomy community was speculating on what may have caused the burs -- perhaps a collision of two older black holes or two neutron stars.

"We are combing the region around the burst with the Keck Telescope in Hawaii for clues about this burst or its host galaxy," said Dr Shri Kulkarni, from the California Institute of Technology, Pasadena, California, which is affiliated to NASA.

Kulkarni is a widely known to be a gamma-ray burst expert.

"What we are seeing so far is what proponents of the merger theory have been saying all along," Kulkarni added.

NASA said that gamma-ray bursts are the most powerful explosions in the universe. Bursts lasting more than two seconds have been observed by NASA satellites such as Swift, built to detect and quickly locate the flashes.

Short bursts had remained elusive until May 9, when Swift detected the latest flash.

"Seeing the afterglow from a short gamma-ray burst was a major goal for Swift, and we hit it just a few months after launch," said Dr Neil Gehrels, Swift project scientist at NASA's Goddard Space Flight Center, Greenbelt, Maryland.

"For the first time, we have real data to figure out what these things are," he added.

Most scientists are convinced short and long bursts arise from two different catastrophic origins. The longer bursts appear to be from massive star explosions in very distant galaxies. The shorter ones, less than two seconds and often just a few milliseconds, are the deeper mystery, because they have been too fast for detailed observation.

NASA said the burst appears to have occurred near a galaxy that has old stars and is relatively nearby, about 2.7 billion light years away from Earth.

This is consistent with the theory, NASA said, that short bursts come from older, evolved neutron stars and black holes. In contrast, longer gamma-ray bursts tend to be in young, distant galaxies filled with young, massive stars, remnants of the early universe.