Scientists have recorded the largest black hole merger in history

Scientists have detected gravitational waves from the merger of two supermassive black holes located 10 billion light-years from Earth.

This was reported on the website of the EurekAlert platform, funded by AAAS (American Association for the Advancement of Science) - the largest non-profit scientific organization in the world.

The waves were detected by the LIGO-Virgo-KAGRA (LVK) Collaboration - an international scientific collaboration uniting three major gravitational-wave observatories.

The signal, designated GW231123, was detected on November 23, 2023, as part of the fourth observation run involving LIGO observatories funded by the US National Science Foundation (NSF).

The merger resulted in a black hole with a mass of about 225 solar masses. For comparison: the previous record belonged to a 2021 event (GW190521), where the final mass was 140 solar masses.

The merger of two black holes - one approximately 100 and the other 140 solar masses - involved rapidly rotating objects, close to the limit established by Einstein's general theory of relativity. Such objects do not fit into standard models of stellar evolution.

"We are observing something that cannot be explained in terms of conventional astrophysics," said Mark Hannam, an astrophysicist from Cardiff University and a member of the LVK collaboration. - "These black holes likely formed as a result of mergers of smaller black holes."

For accurate interpretation of the signal, scientists had to use the most advanced models that account for the dynamics of rapidly rotating objects. According to researchers, a complete understanding of the features of this event may take years.

"This is a real challenge for our theoretical and technological capabilities," said Sophie Bini, a researcher at the California Institute of Technology and a collaboration member. - "And at the same time - an exciting opportunity for new discoveries."

The event will be officially presented at the International Conference on General Relativity and Gravitation (GR24) and the Edoardo Amaldi Conference on Gravitational Waves, which will be held on July 14-18, 2025, in Glasgow (UK).

Open data about this merger will be made available to the scientific community through the Gravitational Wave Open Science Center (GWOSC) portal.