Core-collapse supernova explosion
expelling nearly-spherical debris shell.
CREDIT: Bill Saxton, NRAO/AUI/NSF
For the first time, astronomers have found a supernova explosion with properties similiar to a gamma-ray burst, but without seeing any gamma rays from it. The discovery, using the National Science Foundation's Very Large Array (VLA) radio telescope, promises, the scientists say, to point the way toward locating many more examples of these mysterious explosions.
"We think that radio observations will soon be a more powerful tool for finding this kind of supernova in the nearby Universe than gamma-ray satellites," said Alicia Soderberg, of the Harvard-Smithsonian Center for Astrophysics.
The telltale clue came when the radio observations showed material expelled from the supernova explosion, dubbed SN2009bb, at speeds approaching that of light. This characterized the supernova, first seen last March, as the type thought to produce one kind of gamma-ray burst. (read more)