science & techESA/Hubble2011

A nearby spiral galaxy may have hosted a gamma-ray burst unlike any known type

the gist

ESO 580-49 looks like a calm spiral galaxy, about 185 million light-years from Earth. In October 2011, however, a gamma-ray burst, a short and extremely energetic flash of gamma rays, was detected from the part of the sky where the galaxy sits. Astronomers estimate that a chance alignment of this kind would be roughly one in ten million, so the galaxy is very likely the burst's host. At this distance it ranks as the second-closest gamma-ray burst ever recorded. Known causes of such bursts, such as the collapse of massive stars or the merger of compact objects, do not seem to fit the evidence well. The researchers have therefore suggested that the event may belong to a new, not yet characterised class of explosion.

so what

Gamma-ray bursts are among the most energetic events in the universe, and a burst that defies known explanations points to gaps in our understanding of how the most violent explosions happen.

ESA/Hubble · CC BY 4.0

Image: ESA/Hubble & NASA