Astronomers study black hole ejections and starless galaxies

Astronomers have provided new insights into cosmic phenomena involving supermassive black holes and starless galaxies. Researchers from the University of California, Santa Barbara, and the University of Texas at Austin have reconstructed a violent event that likely ejected a supermassive black hole, designated RBH-1, from its host galaxy. By simulating hundreds of thousands of black hole pairs, scientists determined that the ejection was caused by a highly asymmetrical merger of two rapidly spinning black holes, which produced a gravitational recoil of nearly 1,000 km/s.

In a separate discovery, astronomers using the Gran Telescopio Canarias (GTC) are investigating Cloud 9, a potential candidate for the first known galaxy without stars. While typical galaxies contain stars, gas, and dust, Cloud 9 appears to contain hydrogen gas and dark matter without emitting starlight. This observation supports cosmological models suggesting the existence of dark matter halos that fail to form stars due to the balance of gravity and radiation heating.