A dead star suddenly came back to life

Scientists at Cornell University (USA) have observed for the first time how a dead star suddenly “comes back to life” after an explosion, becoming the source of repeated explosions of unknown nature observed over several months. The findings are reported in a paper published in the journal Nature. Scientists have discovered for the first time a rare type of stellar catastrophe called a fast blue light transient (LFBOT). After 100 days, astronomers observed a bright, short burst that lasted only a few minutes and was as bright as the initial explosion in what appeared to be the remains of the star. Analysis of long-term observations confirmed the presence of at least 14 irregular light pulses over 120 days, but this is likely only a small fraction of the total.

The explosion was officially named AT2022tsd and was nicknamed the “Tasmanian Devil.” It has been speculated that the previously unknown flare activity may be caused by stars leaving behind neutron stars or black holes after exploding. Additionally, LFBOT may have formed from the merger of a star and a black hole, rather than a regular supernova.

source: https://www.nature.com/articles/s41586-023-06673-6