The massive black hole has been dubbed GW231123. Its unusual size and behavior is challenging scientists' understanding of black hole formation, Hannam said. Previously, the largest known black hole that came from a merger was about 140 times the mass of the sun.

New gravitational wave findings from the LIGO-Virgo-KAGRA Collaboration report the discovery of the largest black hole merger ever. It could lead to evidence of an extremely rare type of black hole.