Discovery could be an important step forward in unlocking secrets about intermediate-mass black holes.
In the heart of Omega Centauria huge cluster of gravitationally bound stars more than 17,000 light-years away, astronomers have just discovered evidence for an entire swarm of stellar-mass black holestells the
“We have long known about the existence of supermassive black holes in the centers of galaxies and black holes of lower stellar mass in our own galaxy. However, the idea of intermediate mass black holesor IMBH, that could bridge the gap between these extremes, has not yet been proven”, explains the astrophysicist Andrés Bañares Hernández.
“By studying Omega Centauri — a remnant of a dwarf galaxy — we were able to improve our methods and take a step forward in understanding the existence of such black holes and the role they can play in the evolution of star clusters and galaxies. This work helps resolve a debate that has lasted two decades and opens new doors for future exploration,” says Hernández.
And there may even exist in Omega Centauri an orbit around a invisible central mass — a hidden IMBH. One published earlier this year pointed out the size of this mass to 8,200 solar masses.
Stellar-mass black holes could be bound, like other stars, by the IMBH’s gravity. What if IMBHs form from hierarchical mergers of stellar-mass black holes, finding both together could be a clue about how giant black holes grow.
“The hunt for the elusive intermediate-mass black holes continues. There may still be one at the center of Omega Centauri, but our work suggests that must be less than 6000 times the mass of the Sun and live next to a cluster of stellar-mass black holes”, says the astrophysicist at the University of Surrey Justin Read.
“There is, however, every chance that we will find one soon. More and more pulsar accelerations are coming, which allows us to peer into the centers of dense star clusters and search for black holes with more precision than ever before,” he concludes.
