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Black holes Tempers are like little children. They spill food all the time, but ESA’s XMM-Newton caught a black hole in the process of ‘flipping over the table’ during an otherwise decent meal.
Hubble image of Marcion 817
This process prevents galaxies around the black hole from forming new stars, giving us insight into how black holes and galaxies evolve together.
At the center of every large galaxy is a supermassive black hole, whose immense gravity pulls in gas from its surroundings. As the gas moves inward, it accumulates in a flat ‘accretion disk’ around the black hole, where it becomes hotter and brighter. Over time, the gas closest to the black hole passes the point of no return and collapses.
However, black holes consume only a fraction of the gas accreting towards them. During a black hole’s orbit, some matter is thrown back into space, much like a dirty child throws away many of the things on its plate.
In more dramatic episodes, a black hole will flip over the entire dinner table: gas in the accretion disk is ejected in all directions at such high speeds that it wipes out the surrounding interstellar gas. Not only does this deprive the black hole of food, it also means that no new stars can form over a large area, changing the composition of the galaxy.
Until now, this super-fast ‘black hole wind’ had only been detected coming from very bright accretion discs, which are at the limit of how much matter they can ingest. this time, XMM Newton Clearly the average galaxy was found to have very strong winds that you could say were ‘just snacking’.
“If the fan is turned on at its highest setting, you can expect very strong winds. In the galaxy we studied, Markarian 817, the fan was turned on at a low power setting. , but there were still incredibly energetic winds,” noted undergraduate researcher Miranda Zak (University of Michigan), who played a lead role. research
“It is very unusual to observe extremely strong winds, and even less common to detect winds that have enough energy to change the character of their host galaxy. In fact, Markerian 817 has been around for about a year. produced these winds, even though they were not particularly active, suggesting that black holes can reshape their host galaxies much more than previously thought,” co-author Elias, astronomer at Roma Tree. Common says. University, Italy.
X-rays are blocked by air.
Active galactic centers emit high-energy light, including X-rays. Markarian 817 stood out to researchers because it was extremely quiet. Observing the Galaxy Using NASA cry fast Observatory, Miranda explains: “The X-ray signal was so weak that I was convinced I was doing something wrong!”
Follow-up observations using ESA’s more sensitive X-ray telescope XMM-Newton revealed what was really going on: the super-fast winds from the accretion disk were acting like a shroud, trapping the nearby X-ray atmosphere. X-rays being sent out were being intercepted. A black hole (called a corona). These measurements were backed up by NASA observations. Nostar Binoculars
Artist’s impression of Markarian 817
Detailed analysis of the X-ray measurements shows that, far from sending up a ‘puff’ of gas, the center of Markerian 817 produced a strong storm over a wide area in the accretion disk. The wind lasted for several hundred days and consisted of at least three distinct components, each moving at several percent of the speed of light.
This solves an open puzzle in our understanding of how black holes and their surrounding galaxies interact. There are many galaxies – including the Milky Way – that have large regions around their centers in which very few new stars form. This can be explained by black hole winds that sweep away star-forming gas, but this only works if the winds are strong enough, persist long enough, and the activity of the black holes Born with normal levels of
“Many outstanding problems in the study of black holes are a matter of detection through long observations that span several hours to capture significant events. This highlights the critical importance of the XMM-Newton mission for the future. ESA Norbert Schartel, XMM-Newton project scientist, says that no other mission can offer the combination of its high sensitivity and the ability to make long, uninterrupted observations.
Source: European Space Agency
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