Ultramassive Black Hole Discovered To Be 33 Billion Times More Massive Than the Sun – Slashdot
Researchers have discovered one of the most massive black holes ever discovered, clocking in at around 32.7 billion times the mass of the sun. It’s located in a galaxy at the center of a massive cluster named Abell 1201, some 2.7 billion light-years away. ScienceAlert reports: The new figure exceeds previous estimates by at least 7 billion solar masses, demonstrating the power of curved light for measuring masses with precision. One way we can find these black holes is looking for an effect called gravitational lensing. This occurs when space-time itself is warped by mass; imagine space-time as a rubber sheet, and the mass as a heavy weight on it. Any light traveling through that region of space-time has to travel along a curved path, and that can look very interesting to an observer watching from afar. […]
The central galaxy, or brightest cluster galaxy (BCG) of Abell 1201, is a large, diffuse elliptical galaxy well-known as a strong gravitational lens. A galaxy far beyond the BCG appears alongside it as an elongated smear, like an eyebrow closely wrapped around its outskirts. This smear was discovered in 2003; in 2017, astronomers found a second, fainter smear, even closer to the galactic center. This implies, astronomers proposed, the presence of a very large black hole at the center of the BCG, but the data available was not detailed enough to resolve the central mass, or reveal more about what was in there.
[Researchers] not only had access to more recent observations, but devised the tools to understand them. They conducted hundreds of thousands of simulations of light moving through the Universe, altering the mass of the black hole at the galaxy’s center, looking for results that replicate the lensing we observe with Abell 1021 BCG. All but one of their models preferred a massive black hole at the center of the galaxy; and the best fit for the mass of that black hole was 32.7 billion times the mass of the Sun. That pushes it well into ultramassive territory, black holes more massive than 10 billion Suns, and close to the theoretical upper limit for black hole masses of 50 billion Suns.
The research has been published in the Monthly Notices of the Royal Astronomical Society.