'Surprising and exciting': U. astronomers harness NASA telescopes for black hole discovery

Key Points:

• University of Utah astronomers used archival data from NASA's Hubble Space Telescope and observations from the James Webb Space Telescope to identify the first stellar-mass black hole, named oMEGACat BH-2, in the Omega Centauri globular star cluster.
• The discovery challenges existing models, as Omega Centauri was expected to contain about 10,000 stellar-mass black holes, but none had been detected until this study employed precise astrometry to track star movements over 20 years.
• The black hole has a lower-than-expected mass of 4.46 solar masses and forms a binary system with a visible star, which has the longest known orbital period for a black hole binary at 94 years.
• Findings suggest the binary system was dynamically formed within the cluster and will likely be disrupted within a billion years, much shorter than the cluster's age of approximately 12 billion years.
• Researchers plan to continue searching for similar black hole systems in Omega Centauri and other clusters, anticipating future discoveries with upcoming missions like NASA's Nancy Grace Roman Space Telescope.