After years of studying the Andromeda Galaxy, the Milky Way’s next-door galaxy, astrophysicists at the University of Utah have noticed an interesting phenomenon: a globular cluster of stars and celestial objects that, according to their predictions, may be hiding a rare species of Black Hole not found in the Milky Way galaxy. Astrophysicists had dubbed this globular cluster Bo23-Go78 found about 2.5 million light-years away with a mass of over 6 million suns. The black hole is found on the outer part of the Andromedia Galaxy.
“The most interesting thing about this Intermediate Mass Black Hole (IMBH) is its location—it is in a massive star cluster around Andromeda that we think is actually the core of a former dwarf galaxy whose outskirts were stripped away by Andromeda’s gravity,” says astrophysicist Anil Seth. “Based on previous work in higher mass stripped nuclei, simulations, and this work, it seems like these stripped galaxy nuclei may actually be the most common environment for IMBHs.
This rare species of black hole is coined as the “Intermediate Mass Black Hole” which can be seen as a “middle ground” between a stellar-mass (relatively small) black hole and a supermassive (gargantuan) black hole. According to astronomer Isaac Schultz, these black holes “are typically 10 to 100 times the mass of our sun and hardly any intermediate mass black holes have been confirmed in the astrophysical record”. While these types of black holes have been detected by X-rays and gamma rays, none have been founded until now.
Astrophysicist Renuka Pechetti uses the distribution of mass of the Bo23-Go78 cluster to deduce that the cluster is more like a stripped nucleus. The black hole was creating the speeds of the moving stars. “The stellar velocities we are getting gives us direct evidence that there’s some kind of dark mass right at the center”, he says in a report to John Moores University in Liverpool. “It’s very hard for globular clusters to form big black holes. But if it’s in a stripped nucleus, then there must already be a black hole present, left as a remnant from the smaller galaxy that fell into the bigger one.”
The next steps, according to Pechetti, involve studying other global clusters to find any correlation or similar activity. “More research must also be conducted on how these types of black holes evolve. If stellar-mass black holes somehow end up as supermassive black holes later on, perhaps the intermediate-mass black holes are just a brief stage in that evolution”. Still, this observation is a massive step in studying the paranormal conundrum that is our universe.