Astronomers have uncovered hundreds of concealed supermassive black holes, offering a glimpse into the vast population of these enigmatic objects thought to populate the universe, Llive Science
reports.
By using advanced infrared imaging techniques, researchers have identified black holes obscured by clouds of gas and dust, a discovery that could reshape our understanding of galaxy evolution and cosmic phenomena.
Black holes, among the universe’s darkest and most elusive entities, are typically identified by the glowing matter they devour. This material, accelerated by intense gravitational forces, emits light that astronomers can observe. However, not all black holes are this conspicuous. Many are shrouded by gas and dust clouds, making them invisible to traditional observational methods.
A new study published in the Astrophysical Journal on December 30, 2024, estimates that approximately 35% of supermassive black holes are obscured in this way, a sharp increase from earlier estimates of 15%. Some researchers suggest the true figure could be as high as 50%.
Supermassive black holes, which are at least 100,000 times the mass of the Sun, are believed to exist at the centers of most large galaxies, including the Milky Way. While their total number remains speculative, scientists hypothesize there could be billions or even trillions scattered throughout the universe.
Despite their concealment, black holes surrounded by gas and dust emit infrared light, allowing astronomers to detect them indirectly. In this study, researchers combined data from NASA’s Infrared Astronomical Satellite (IRAS), which briefly operated in 1983, and the Nuclear Spectroscopic Telescope Array (NuSTAR), an X-ray telescope designed to detect high-energy emissions from superheated matter.
Using IRAS archival data, astronomers identified hundreds of likely hidden black holes. Follow-up observations with ground-based optical telescopes and NuSTAR helped confirm many of these findings, while others turned out to be star-forming galaxies.
