spacetoday.net: Gamma-ray burst marks death of giant star

Posted: Thu, Mar 20, 2003, 10:31 AM ET (1531 GMT)
GRB collapsar illustration (NASA/GSFC)

Astronomers who observed a gamma-ray burst (GRB) from its early stages believe that the burst marks the collapse of a giant star into a black hole. A GRB was spotted by NASA's High-Energy Transient Explorer (HETE) spacecraft on October 4, 2002; the spacecraft alerted astronomers, who trained telescopes on the location of the burst within several minutes. Those observations showed the optical afterglow of the burst was powered by energy from the burst for at least a half-hour, and the energy of the GRB overall was several times greater than previously thought. This led astronomers to conclude that the burst originated from the death throes of a star 15 times as massive as the Sun, a method known as the collapsar model. They believe the core of the massive star may have collapsed into a black hole. The findings have been published in the latest issue of the journal Nature.