ASTRONOMERS said yesterday they have identified the “largest” cosmic explosion ever observed, a fireball 100 times the size of our solar system that suddenly began blazing in the distant universe more than three years ago.

While the astronomers offered what they think is the most likely explanation for the explosion, they emphasised that more research was needed to understand the puzzling phenomenon.

The explosion, called AT2021lwx, is not the brightest flash ever observed in the universe. That record is still held by a gamma-ray burst in October that was nicknamed BOAT – for Brightest Of All Time. 

Philip Wiseman, an astrophysicist at Britain’s University of Southampton and the lead author of a new study, said that AT2021lwx was considered the “largest” explosion because it had released far more energy over the last three years than was produced by BOAT’s brief flash.

Wiseman told AFP it was an “accidental discovery”.

The Zwicky Transient Facility in California first spotted AT2021lwx during an automated sweep of the sky in 2020.

But “it basically sat in a database” until being noticed by humans the following year, Wiseman said. – AFP, May 12, 2023.