Astronomers have found high-energy x-ray evidence for five hidden supermassive black holes in the Universe that were previously clouded from direct view by dust and gas.

The research, led by astronomers at the Centre for Extragalactic Astronomy at Durham University, UK, supports the theory that potentially millions more supermassive black holes exist in the Universe, but are hidden from view, according to the astronomers.

Using NASA’s Nuclear Spectroscopic Telescope Array (NuSTAR) satellite observatory, the scientists observed nine candidate hidden supermassive black holes that were thought to be extremely active at the center of galaxies, but where the full extent of this activity was potentially obscured from view. High-energy X-rays are more penetrating than low-energy X-rays, so the astronomers can see deeper into the gas burying the black holes.

“For a long time we have known about supermassive black holes that are not obscured by dust and gas, but we suspected that many more were hidden from our view,” said George Lansbury, a postgraduate student at Durham University, lead author of a paper to be published in Astrophysical Journal. Although we have only detected five of these hidden supermassive black holes, when we extrapolate our results across the whole Universe then the predicted numbers are huge and in agreement with what we would expect to see.”

The research was funded by the Science and Technology Facilities Council (STFC). The findings were presented early today (July 6) at the Royal Astronomical Society’s National Astronomy Meeting, at Venue Cymru, in Llandudno, Wales .