Radiation Blast That Hit Earth Was Record-Breaking Energy Burst From Dying Star

Scientists have detected a record-breaking blip of high-energy radiation from a collapsing star.

Using NASA's Fermi Gamma-ray Space Telescope, astronomers picked up what is known as a gamma-ray burst, or GRB, that had raced towards Earth from deep space. It has been named GRB 200826A.

GRBs are typically created when something incredibly energetic happens somewhere in space, and are divided into two types—long GRBs and short GRBs.

Short GRBs are generated when two dense stars, or even a star and a black hole, join together in an event that can be as rapid as two seconds or less. Long GRBs are generated when massive stars collapse.

But GRB 200826A, detected in August 2020, surprised scientists because it was short but also appears to have come from the collapse of a star.

It's thought to be the shortest GRB ever detected that has been produced in this way.

It was also incredibly powerful. The amount of energy emitted by that single gamma-ray burst was equal to all of the energy released by the entire Milky Way galaxy over the same time period—multiplied by 14 million times.

Tomás Ahumada, a doctoral student at the University of Maryland who co-authored a research paper about GRB 200826A, said it was one of the most energetic short-duration GRB's ever documented.

Stars collapse when they run out of hydrogen—the fuel that keeps them burning. Without this fuel, they begin to fall into themselves because of their huge internal mass.

As the material inside the star rushes in on itself, it releases two powerful jets of radiation in opposite directions. If one of these jets is pointed directly at the Earth, scientists can detect it with specially-designed telescopes and work out where in the universe it came from.

After detecting GRB 200826A, astronomers studied the patch of sky the burst seemed to have come from and saw that it came from a galaxy 6.6 billion light years away, meaning the gamma-ray burst would have taken around half the age of the universe to reach us.

The astronomers also found the afterglow from the star's collapse, known as a supernova, which suggested the source of the GRB was indeed a collapsing star and not a binary merger event typically associated with short GRBs.

The shortness of the burst also suggests that the star only just managed to produce them, which may help scientists explain why they spot many more supernovae than they do GRBs. Ahumada's report, published in the journal Nature Astronomy on Monday, concludes: "Our discovery is consistent with the hypothesis that most collapsars fail to produce ultra-relativistic jets."

Radio telescopes
Radio telescopes seen at the Mullard Radio Astronomy Observatory in the U.K., July 2006. Scientists detect gamma-ray bursts from deep space using special telescopes. Damian Gillie/Construction Photography / Avalon / Getty