A supermassive black hole in the early universe is at least 10 times too heavy for its host galaxy, raising questions about galaxy and black hole coevolution.
CID-947 is a supermassive black hole that’s visible across the observable universe because it’s actively gobbling down gas and spitting out radiation. It’s a classic quasar in every way except one: its supermassive black hole is too heavy for its galaxy.
Over the past decade, astronomers have discovered that supermassive black holes have a scaling relationship with their host galaxies: the more massive the black hole, the more massive the galaxy. On average, a supermassive black hole has a mass 1/100 to 1/1,000 times that of its host galaxy. Seemingly consistent relationships like this one have led astronomers to suspect that a black hole’s growth and its host galaxy’s growth are intertwined.
But CID-947 doesn’t lie anywhere near this relation. At 2 billion years after the Big Bang, this quasar only weighs eight times less than its host galaxy.
