By Ron Cowen
The mass of the most distant black hole known has been measured, and it’s a behemoth. The black hole lies some 13 billion light-years away and weighs the equivalent of 3 billion suns, researchers report in the April 10 Astrophysical Journal Letters.
To weigh the hole, astronomers examined light from the most remote quasar ever detected. According to theory, quasars are powered by supermassive black holes.