Two Theories Offered In Christmas Burst
December 1, 2011 by UPI - United Press International, Inc.
WASHINGTON, Nov. 30 (UPI) — A cosmic explosion dubbed the Christmas burst was caused either by a far away supernova or an unusual collision closer to home, U.S. space officials said.
NASA said papers describing both interpretations of the explosion — first spotted on Christmas Day 2010 by NASA’s Swift Observatory — are published in the Dec. 1 issue of Nature.
Gamma-ray bursts emit more energy in a few seconds than the sun will during its entire energy-producing lifetime, astronomers said.
“What the Christmas burst seems to be telling us is that the family of gamma-ray bursts is more diverse than we fully appreciate,” Christina Thoene of the Institute of Astrophysics of Andalusia in Granada, Spain, said Friday in a release. “It’s only by rapidly detecting hundreds of them, as Swift is doing, that we can catch some of the more eccentric siblings.”
Thoene’s team suggests the burst occurred in a binary system where a neutron star orbited a normal star that had just entered its red giant phase, enormously expanding its outer atmosphere. The expansion engulfed the neutron star, resulting in both the ejection of the giant’s atmosphere and rapid tightening of the neutron star’s orbit.
The interpretation suggests the event took place about 5.5 billion light-years away.
Sergio Campana, who led the second study at Brera Observatory in Merate, Italy, said his team’s research supports a theory that the burst came from a collision between debris from a large comet-like object onto a neutron star located about 10,000 light-years away.
“The beauty of the Christmas burst is that we must invoke two exotic scenarios to explain it, but such rare oddballs will help us advance the field,” said Chryssa Kouveliotou, a co-author of the supernova study at NASA’s Marshall Space Flight Center in Huntsville, Ala.