A brilliant flash of high-energy radiation recorded on Feb. 22 lasted for less
than a minute. But this gamma-ray burst, one of the brightest ever detected, is
providing the strongest evidence so far that these cosmic flashbulbs originate in
star-forming regions of distant galaxies and are generated by the explosive death
of massive stars.
The findings support the notion that these brilliant bursts and their afterglows
can enable astronomers to study galaxies that lie too far away and are too dusty
for the scientists to easily observe.
The Feb. 22 burst and its X-ray afterglow, first detected by the Italian satellite
BeppoSAX, was also examined by NASA's Chandra X-ray Observatory. The burst
originated in a galaxy some 8 billion light-years from Earth.
A gamma-ray burst produces a blast of material that expands into surrounding space
like a rapidly inflating balloon. This expanding blast wave produces a steady