In the case of Phoenix A, it has been shown to have a estimated mass on the order of 100 billion M☉, possibly even exceeding this mass. Such a high mass makes it one of the most massive black holes known in the universe. A black hole of this mass has: 24,100 times the mass of the black hole at the center of the Milky Way (Sagittarius A*) twice the mass of the Triangulum Galaxy, including its dark matter halo Phoenix a, is mostly calm, and generally likes to be quiet and not disturb others.