Strange Christmas Space Explosion

Imaged Above: Artist’s impression of the model suggested for GRB 101225A

Credit: Aurore Simonnet, NASA E/PO, Sonoma State University

Competing Explanations Proposed for Strange Christmas Space Explosion

The Christmas sky last year was lit up by an extraordinarily powerful and mysteriously long-lasting explosion in space that scientists now suggest was a comet smacking into a dense star or a peculiar supernova death.

Radiation from gamma-ray bursts, the most powerful explosions ever seen in the universe, strikes Earth’s atmosphere from random directions in space about twice a day. These bursts can be roughly divided into two kinds, ones lasting less than two seconds, and ones lasting up to minutes.

However, the strange gamma-ray burst detected on Christmas Day 2010 by NASA’s Swift satellite lasted at least half an hour.

Scientists think shorter gamma-ray bursts are generally caused by merging neutron stars — dead stars made up of super-dense neutron matter. Longer bursts are typically thought to originate from hypernovas, in which giant stars that explode as incredibly powerful supernovas spew two opposing jets of energy as they die; we see them head-on as bursts.