Astronomers have been left baffled by a mysterious flash of X-rays captured by Nasa’s Chandra X-ray Observatory in deep space. 

The source of the flash is in a region of the sky known as the Chandra Deep Field-South (CDF-S), which scientists say erupted just in October 2014, becoming 1,000 times brighter within a matter of hours.

Stuff.co.nz reports:

After about a day, the source had faded to the point that it couldn’t be detected by Chandra.

“Ever since discovering this source, we’ve been struggling to understand its origin,” said Franz Bauer of the Pontifical Catholic University of Chile in Santiago, Chile.

“It’s like we have a jigsaw puzzle but we don’t have all of the pieces.”

Two of the three main possibilities to explain the X-ray source invoke gamma-ray burst (GRB) events. GRBs are jetted explosions triggered either by the collapse of a massive star or by the merger of a…