Astronomers have detected the largest-ever collision between two black holes, each with masses 100 and 140 times that of our sun. The merger, dubbed GW231123, was observed using the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Louisiana and Washington.
According to Einstein’s theory of general relativity, gravity causes objects to move through curved space-time, producing ripples known as gravitational waves. These waves were predicted by Albert Einstein in 1915 but remained undetectable until LIGO detected them for the first time in 2016.
The GW231123 event is significant because it lies in a “mass gap” – a range of masses where scientists believe black holes cannot form through normal stellar collapse. The individual black holes are thought to have spun almost as fast as physically possible, presenting a challenge to our understanding of their formation.
Researchers suggest that the massive black holes may be the result of previous mergers rather than the product of dying stars. This idea is supported by the high spin rate of the black holes and would reveal an unexpected population of black holes with masses in between those formed from stellar collapse and supermassive black holes.
The discovery of GW231123 highlights the importance of gravitational wave astronomy, which has opened a new window into the formation and growth of black holes. Future detections will help determine whether this event was a one-off or part of a larger phenomenon.
Source: https://edition.cnn.com/2025/07/16/science/massive-black-hole-collision-gravitational-waves