Found evidence of the existence of a large population of supermassive black holes

Supermassive black hole, hidden by a gas and dust cloud (artist presentation) / NASA / ESA

An international team of astronomers led by British scientists from the Royal Astronomical Society (Royal Astronomical Society, RAS) discovered high-energy X-rays , which were given out by five supermassive black holes. Previously, these objects were hidden from astronomers' gaze by cosmic dust and gas.

The discovery was made with the help of the Nuclear Spectroscopic Telescope Array (NuSTAR) - NASA's space observatory program of small space satellites. This is the space telescope of the hard X-ray range (7-80 keV), which operates on the principle of sliding reflection — reflections of x-rays and gamma rays at very small angles to the surface of the mirrors. It was launched into orbit in 2012.
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It was not by chance that black holes were found - the experiment was supposed to test the theory that in the centers of galaxies there are extremely active black holes that are hidden from ordinary observations by dust and gas clouds.

Before the NuSTAR telescope was commissioned, this kind of observation was impossible. Now, having collected data from nine points of the sky, where black holes could potentially be present, a team of researchers found five objects of interest. These black holes are more active than scientists supposed - they quickly absorb surrounding matter and emit powerful radiation fluxes.

“We have long been able to observe several black holes not hidden by dust and gas, but we suspected that there were a much larger number hidden from our observations,” says George Lansbury, a graduate student at the Center for Extragalactic Astronomy at Durham University. “Thanks to NuSTAR, we first discovered these hidden monsters that we had not seen before.”

Extrapolation of the obtained results suggests that there are huge numbers of such black holes in the Universe - much more than was considered on the basis of past observations.

Daniel Stern, a representative of the telescope team, said: “ High-energy X-rays penetrate further than low-energy ones, so we can penetrate deeper into the clouds of gas and dust. NuSTAR will help us, first, to estimate the size of black holes, and secondly, to figure out why only some of them are hidden by these clouds. ”