Astronomers have identified a black hole that may have formed in a gentler process than a supernova, as part of a triple system.

The black hole, called V404 Cygni, has been observed in a triple system, gravitationally bound to two stars. This shows that some binary systems with a black hole and an ordinary star may have initially formed as a triple system, with the black hole subsequently swallowing one of the stars, a gentler process than supernovae.