Astronomers have made an accidental discovery of the “largest” cosmic explosion ever observed, which occurred over three years ago. The fireball is 100 times the size of our Solar System and is estimated to be around two trillion times brighter than the Sun. The explosion, named AT2021lwx, was first spotted by the Zwicky Transient Facility in California during an automated sky sweep in 2020. It went unnoticed until it was noticed the following year by humans, who then realized they had something extraordinary on their hands.
Despite the astronomers offering explanations for the explosion, such as it being an exploding star or a tidal disruption event, they have emphasized that further research is needed to understand the puzzling phenomenon. The explosion released far more energy over the last three years than was produced by the previous brightest flash ever observed in the universe, called BOAT. The astronomers believe it is the most likely scenario that a massive, single cloud of gas is slowly being consumed by a supermassive black hole.
The team of researchers who have laid out their theory in a study published in the Monthly Notices of the Royal Astronomical Society are working on new simulations to see if their theory is fully plausible. One problem could be that for an explosion this size, the galaxy would be expected to be as vast as the Milky Way. However, no one has been able to spot a galaxy in the vicinity of AT2021lwx. As such, the team is uncertain whether their theory is correct.
Astronomers are now searching the skies to see if other similar explosions have been missed. The discovery has opened up new opportunities for astronomers to study cosmic explosions and phenomena. Although no one can be certain about the exact cause of this extraordinary explosion, it is clear that it has captivated the scientific community and is leading to new discoveries and insights into our universe.