Infrared reveals hidden supermassive black holes

University of Cambridge scientists have discovered a new set of enormous, rapidly growing supermassive black holes in the early universe.

They are hidden by thick layers of dust, but are emitting vast amounts of radiation through violent interactions with their host galaxies, and were detected using new, cutting edge infrared surveys being carried out on the UK Infrared Telescope (UKIRT).  

The most extreme object in the study is a supermassive black hole called ULASJ1234+0907, 11 billion light years away. It’s more than 10 billion times the mass of our sun, 10,000 times greater than the supermassive black hole in our own Milky Way, making it one of the most massive black holes ever seen.

The team says there may be as many as 400 such giant black holes in the observable universe.

“These results could have a significant impact on studies of supermassive black holes,” says Dr Manda Banerji. “Although these black holes have been studied for some time, the new results indicate that some of the most massive ones may have so far been hidden from our view.”

The newly-discovered black holes, which devour the equivalent of several hundred suns every year, will shed light on the physical processes governing the growth of all supermassive black holes, says the team.

“These new quasars are important because we may be catching them as they are being fed through collisions with other galaxies,” says Professor Richard McMahon.

“Observations with the new Atacama Large Millimeter Array (ALMA) telescope in Chile will allow us to directly test this picture by detecting the microwave frequency radiation emitted by the vast amounts of gas in the colliding galaxies.”