University of Leicester scientists explore 'brightest' cosmic explosion ever detected
Scientists from the University of Leicester have been part of a worldwide team investigating the ground-breaking discovery of the brightest gamma-ray burst ever detected.
A cosmic explosion, two billion light years from Earth, blinded space instruments when it produced an intense pulse of radiation that swept through the solar system in October 2022.
Scientists, including those on NASA’s Swift mission, said this type of event is a gamma-ray burst (GRB) - known for being some of the strongest and brightest explosions in the universe.
This GRB was deemed so exceptional that astronomers described it is the brightest of all time since the beginning of human civilisation.
This meant astronomers could not measure the real intensity of the emission and had to reconstruct its energy expenditure from past and present data.
An analysis of 7,000 GRBs suggests that GRB 221009A is 70 times brighter than any yet seen, and an event like this occurs once every 10,000 years.
"This is physics that you can't do in a lab"
Dr Phil Evans, University of Leicester X-ray astronomer, described the team's excitement on studying the cosmic boom.
He says:
"What we've discovered with a variety of satellite instruments, is the brightest gamma ray burst ever seen, like ten to a hundred times brighter than ever seen before.
"Gamma ray bursts are the most powerful explosions known in the universe and they happen when a star reaches the end of its life, the centre causes a black hole and the outer layer gets blown off.
"This was so bright we didn't even think it was a gamma ray burst ... so when you get something this bright it's really exciting you can study in real detail.
"This is physics that you can't do in a lab, you can't blow up stars in a lab, strangely enough".
Dr Dan Perley, of the Astrophysics Research Institute at Liverpool John Moores University, followed the event with the University's Liverpool Telescope on the Spanish island of La Palma.
He said:
"There is nothing in human experience that comes anywhere remotely close to such an outpouring of energy. Nothing."
Though they last mere seconds, GRBs produce as much energy as the Sun will emit during its entire lifetime.
Astronomers believe GRB 221009A is a result of a massive star collapsing in on itself to form a black hole.
It is thought that GRB 221009A was so bright because it was much closer to Earth compared to other known GRBs, and the beam of electromagnetic radiation happened to be pointing in the direction of the planet.
The findings have been nicknamed the BOAT (Brightest Of All Time), in a nod to football's GOAT term (Greatest Of All Time).