XMM-Newton discovers a black hole with a “tantrum”

There is one at the heart of every major galaxy supermassive black hole, whose enormous gravity attracts gas from its surroundings. As the gas spirals in, it collects in one Accretion disk Plane around the hole where it will be heated and lit. Over time, the material closest to the black hole passes the point of no return and is engulfed.

However, black holes only consume a fraction of the gas flowing towards them. When you orbit a black hole, Some of the matter is ejected into spacesimilar to how a messy child spills a lot of what’s on his plate.

In more dramatic episodes, the child, or in this case the black hole, can even “flip the table”: that Gas from its accretion disk is ejected in all directions. Its speed is so great that it causes the surrounding interstellar material to disappear. Not only does this deprive the black hole of food, but it can also prevent new stars from forming over a huge area, changing the structure of the galaxy.

So far this is “Ultrafast black hole wind It has only been found to come from extremely bright accretion disks that are at the limit of the amount of matter they can attract. But the space observatory XMM Newton The European Space Agency (ESA) has discovered ultrafast winds in an average galaxy that could be said to be just having a snack.

Fan that blows a lot with little power

“You could expect very fast winds if a fan were on at maximum power. In the galaxy we’re studying, that is.” Markarian 817“The fan was turned on at lower power, but incredibly strong winds were still generated,” says the researcher. Miranda Zak from the University of Michigan (UK), lead author of the study, published in Astrophysical Journal.

Markarian Galaxy 187 as seen from the Hubble Space Telescope. / NASA, ESA, Hubble SM4 ERO Team

“It is very rare to observe ultrafast winds, let alone detect ones that have enough energy to change the character of their host galaxy. The fact that Markarian 817 produced these winds for about a year despite not being particularly active suggests that black “holes can reshape their host galaxies much more than previously thought,” the co-author adds Elias KammounAstronomer at the University of Rome III (Italy).

The fact that Markarian 817 generated these winds for a year without being very active suggests that black holes can reshape their parent galaxies much more than we thought.

Elias Kammoun (Uniroma3)

Active galactic centers emit high-energy light, including X-rays. However, Markarian 817 caught researchers’ attention because of its silence. Miranda watched the galaxy with the Fast Observatory from NASA: “The X-ray signal was so weak that I was convinced I was doing something wrong.”

X-rays are blocked by wind

Follow-up observations with the X-ray telescope XMM Newton, more sensitive, revealed what was really happening: the ultrafast winds coming from the accretion disk acted like a shell, blocking the X-rays sent from the black hole’s immediate surroundings (the so-called corona). These measurements were supported by observations made with the NuSTAR telescope from NASA.

Detailed analysis of the X-ray measurements showed that, far from ejecting a single “puff” of gas, the center of Markarian 817 was generating one gusty storm in a large area of ​​the accretion disk. The wind lasted several hundred days and consisted of at least three different componentseach moving at several percentage points of the speed of light.

This solves an open puzzle in our understanding of how black holes and their surrounding galaxies influence each other and co-evolve.

Influence of winds on conditions

There are many galaxies – including the Milky Way – where this appears to be the case large regions about the centers in which they arise very few new stars. This could be explained by this Winds of black holes ejecting star-forming gas, but this only works when the wind is strong. fast enoughare maintained during the enough time and are produced by black holes with typical levels of activity.

“Many of the outstanding problems in black hole research involve making discoveries through long observations lasting many hours to capture important events. This underlines the outstanding importance of the XMM-Newton mission for the future. “No other mission can offer this combination of high sensitivity and the ability to conduct long, continuous observations,” says Norbert SchartelScientists at this ESA space observatory.