NASA astronomers focus on the number of hidden supermassive black holes

There are likely more supermassive black holes lurking in the universe than we can see, according to a team of scientists who have just confirmed a new estimate of the number of giants hidden from view.

The discovery could help scientists understand how supermassive black holes get so large — billions of times the mass of our Sun — and explain the crucial role black holes play in galactic evolution.

Black holes have gravitational fields so intense that even light cannot escape from their vicinity beyond a certain point – the event horizon of the black hole. But outside the event horizon, the environment around the black hole is so bright, it’s crowded with a pie of super-hot gas and dust known as an accretion disk.

This material sometimes blocks the light that astronomical observatories would see. The team found that about 35% of the supermassive black holes they studied are obscured by the surrounding gas and dust. This result suggests that the number of hidden black holes is greater than previously thought, as previous searches indicated that about 15% of supermassive black holes were so obscured. It was the team’s research published Last month in Astrophysical Journal.

The team reached its conclusions based on data from NASA’s Infrared Astronomy Satellite (IRAS) and the Nuclear Spectroscopic Telescope Array (NuSTAR) X-ray. IRAS captures infrared light (as its name suggests), and infrared emissions from the black hole’s accretion disks reveal whether the black hole is directly facing the satellite, or if its edge is pointed toward the instrument. After identifying a set of hundreds of initial targets using IRAS, the research team used NuSTAR to confirm the presence of edged — that is, obscured — black holes based on their X-ray emissions.

“If we didn’t have black holes, galaxies would be much larger,” said study co-author Boshak Gandhi, an astrophysicist at the University of Southampton, NASA’s Jet Propulsion Laboratory. He releases. “So, if we didn’t have a supermassive black hole in our Milky Way galaxy, there might be more stars in the sky. This is just one example of how black holes affect galaxy evolution.”

Moreover, the influence of black holes can extend far beyond the galaxies in which they reside. Last year, a team of astrophysicists identified The largest known black hole jet– Streams of particles emanating from the body at speeds approaching the speed of light. These jets are called Porphyrion, after a giant of Greek mythology, and their length is at least 140 times greater than the width of the Milky Way.

Black holes are crucial drivers of galaxy evolution, but even these extremely massive objects can evade human detection. Recent research has shown how these hidden black holes stay out of sight, and suggests that there is more to giant cosmic forces than we know about.