Q0906+6930 is the most distant known blazar (redshift 5.47 / 12.2 billion light years), discovered in July, 2004. The engine of the blazar is a supermassive black hole (SMBH) approximately 2 billion times the mass of the Sun (the mass of the Milky Way Galaxy is around 580 billion solar masses). The event horizon volume is on the order of 1000 times that of the Solar System. It is one of the most massive black holes on record.
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