Astronomers witness supernova

Thursday, August 31, 2006

Scientists are studying a strange explosion that appeared on February 18, 2006, about 440 million light years away in the constellation Aries.

Scientists using NASA's Swift Satellite and other telescopes have observed a supernova in near real time occurring in the constellation of Aries. The explosion is said to be the most powerful explosion known to scientists, which consists of a gamma-ray burst or an x-ray blast. Scientists say that bursts signal the beginning of a star's death.

Swift first detected the explosion on February 18 (it was given a designation GRB 060218), which allowed telescopes and satellites to watch the event as it happened. The blast lasted for more than 2,000 seconds (33 minutes).

"This is totally new and unexpected. This is the type of unscripted event in our nearby universe that we hoped Swift could catch," said Neil Gehrels, Swift principal investigator at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

"Those observations capture the time when the star collapsed, ejected its outer envelope and most of its mass and left a compact remnant behind. And we think that compact remnant is a neutron star," said an author writing for journal Nature, where the report will be published on Thursday.

Scientists are also planning on using the Hubble Space Telescope and the Chandra X-ray Observatory in an attempt to get more images of the event.

The star is at least 440 million light years from Earth. The group of scientists was led by Sergio Campana of the Italian National Institute for Astrophysics and Alicia Soderberg, a graduate student at Caltech in Pasadena, California.

Swift was launched in November of 2004.