The blue stars around the supermassive black hole of M31
Research report (imported) 2005 - Max Planck Institute for extraterrestrial Physics
Summary
Hubble Space Telescope observations reveal that the Andromeda galaxy harbours a central supermassive black hole of 140 million solar masses. The new data exclude astrophysical alternatives to a black hole. The black hole is surrounded by a tiny disk of young stars whose origin remains enigmatic.