A supermassive black hole in the center of H1821 + 643, a quasar about 3.4 billion light-years away from Earth, rotates at about half the speed of light.
This composite image of H1821 + 643 contains X-rays of Chandra (blue) that have been combined with radio data from Karl G. Jansky Very Large Array (red) of NSF and an optical image of the PanSTARRS telescope in Hawaii (white and yellow ). Image credit: NASA / CXC / Cambridge University / Sisk-Reynés et al. / NSF / NRAO / VLA / PanSTARRS.
“We estimate that the black hole that is actively growing at H1821 + 643 contains between three and 30 billion solar masses, making it one of the most massive known,” said Júlia Sisk-Reynés of the Astronomical Institute of the University of Cambridge and colleagues. .
“By contrast, the supermassive black hole in the center of the Milky Way has a mass of about 4 million solar masses.”
In their research, astronomers analyzed data from NASA’s Chandra X-ray Observatory.
They found that the supermassive black hole H1821 + 643 is at the bright spot in the center of the radio and X-ray emission.
Because a rotating black hole drags space with it and allows matter to orbit as close as possible to a non-rotating one, X-ray data can show how quickly the black hole rotates.
The spectrum of H1821 + 643 indicates that the black hole rotates at a modest rate compared to other less massive ones rotating close to the speed of light. This is the most accurate turn measurement for such a massive black hole.
“Why does the H1821 + 432 black hole rotate only about half the speed of lower mass cousins? The answer may lie in how these supermassive black holes grow and evolve,” the researchers said.
“This relatively slow turn supports the idea that more massive black holes like H1821 + 643 experience most of their growth by merging with other black holes, or with gas stretching inward in random directions. when their big records are interrupted “.
“Supermassive black holes that grow this way are likely to undergo major changes in rotation, including being slowed down or broken in the opposite direction.”
“The prediction is, therefore, that it should be observed that more massive black holes have a wider range of rotational speeds than their less massive relatives.”
On the other hand, scientists expect less massive black holes to accumulate most of their mass from a gas disk that revolves around them.
“Because these disks are expected to be stable, the incoming matter is always approaching from a direction that will cause the black holes to rotate faster until they reach the maximum possible speed, which is the speed of light.” , said.
The team’s paper was published in the Monthly Notices of the Royal Astronomical Society.
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Júlia Sisk-Reynés et al. 2022. Evidence of moderate rotation from X-ray reflection of the supermassive black hole of high mass in the H1821 + 643 quasar housed in the cluster. MNRAS 514 (2): 2568-2580; doi: 10.1093 / mnras / stac1389