GW231123 Data Released

First published: July 14, 2025

Read the notes for the release of the GW231123_135430 event!

GW231123 is the merger of the most massive black holes ever observed with gravitational waves. The merger produced a final black hole more than 225 times the mass of our Sun. The signal was observed during the fourth observing run (O4) of the LVK network on November 23, 2023.