A team of astronomers has made a remarkable discovery in the heart of our Milky Way galaxy: a rare ‘missing link’ black hole. This discovery solves a longstanding puzzle surrounding the IRS 13 star cluster, located a mere tenth of a light-year from the supermassive black hole Sagittarius A*.
The proximity of IRS 13 to Sagittarius A*’s powerful gravitational pull initially led astronomers to believe it should lack any significant structure. However, observations revealed that the cluster’s hot, massive stars are moving in an orderly pattern, hinting at an unseen force keeping them in line.
This force, according to a study published in The Astrophysical Journal, is an elusive black hole interacting with Sagittarius A*. This intermediate-mass black hole, estimated to be 30,000 times the mass of our sun, explains the cluster’s structure and fills a gap in our understanding of black hole evolution.
Black holes are categorized into stellar-mass black holes (a few to a few dozen times the mass of the sun) and supermassive black holes (millions to billions of times the sun’s mass). Intermediate-mass black holes, theoretically ranging from 100 to 100,000 times the sun’s mass, have remained elusive, with no definitive confirmations until now.
The astronomers used the Very Large Telescope, Atacama Large Millimeter/submillimeter Array, and Chandra X-ray space telescope to observe IRS 13. Their data revealed a seemingly empty space at the cluster’s center, but X-ray emissions from a ring of ionized gas indicated the presence of an accretion disk around a black hole.
This newly discovered black hole provides invaluable insights into the evolution of black holes. Astronomers plan to conduct further observations using the James Webb Space Telescope and the Extremely Large Telescope, aiming to uncover more secrets about the behavior of this intermediate-mass black hole and its role in the larger cosmic picture.
