Galactic Merger Kicks Supermassive Black Hole Into Intergalactic Space

Physicists have determined that a galactic merger kicked a supermassive black hole, named RBH-1, into intergalactic space, marking the first observed instance of such an ejection. Researchers at UCSB and UT Austin traced RBH-1 back to its origin using Hubble and James Webb Space Telescope data, concluding a merger of two misaligned, rapidly spinning black holes produced a gravitational wave recoil strong enough to launch it. Their findings were published in Physical Review Letters. The ejected black hole is traveling at nearly 1,000 km/s, leaving a 200,000-light-year trail of young stars. This discovery supports predictions that 5-10% of galactic mergers eject black holes, and future observatories like LISA may help study the low-frequency gravitational waves involved.