The gigantic eruption of this black hole created 19 huge

The gigantic eruption of this black hole created 19 huge star clusters!

When we think of black holes, and especially those that are supermassive and have at least a million solar masses and sometimes more than 10 billion, we think of cosmic monsters that devour stars or intergalactic streams of matter. In both cases, accretion disks form around giant black holes, where matter spirals into a disk, creating frictional forces due to the viscosity of the gas. The heat released can be so great that the gas becomes a plasma at a very high temperature and therefore radiates abundantly in the X-ray range.

Matter falls not on just any black hole, but on a rotating Kerr black hole. Complex magnetohydrodynamic processes, such as those that occur on the surface of the SunSun, also take place in the disk that forms a ring around the black hole, or in the more inner part of the flow of matter, leading to particle jets, but sometimes also to instabilities of powerful eruptions similar to those the sun.

Jean-Pierre Luminet, research director at CNRS, and Françoise Combes, professor at the Collège de France, tell us about black holes, especially the large supermassive black holes in galaxies that are behind quasars and influence the evolution of galaxies. © Hugot Foundation of the Collège de France

A black hole in a giant galaxy at the heart of a galaxy cluster

A team of astronomers, including Françoise Combes, announced in an article on arXiv that they had discovered one of the most powerful black hole bursts ever recorded. Paradoxically, the destructive power of this mega-explosion became a creative force, indirectly causing the collapse of several clouds of gas and dust several billion years ago, giving rise to 19 superclusters of stars.

In the obtained images, which combine observations at multiple wavelengths, these superclusters are arranged in an “S” shape reminiscent of beads on a string. These images show the galaxy cluster SDSS J1531+3414 (SDSS J1531 for short) as it looked 3.8 billion years ago, about 200 million years after the superflare.

It occurred around one of the supermassive black holes found in two of the giant galaxies that are usually found at the heart of galaxy clusters and which in this case are observed colliding. In this case, several instruments were used, including NASA's ChandraChandra X-ray observatory and the Low Frequency Array (Lofar), a radio telescope.

Grant Tremblay, who was involved in this study, summarizes the discovery in a NASA press release: “We have reconstructed a likely sequence of events in this cluster that occurred over a wide range of distances and times.” It all started with a black hole a tiny fraction of a light-year across that formed a cavity nearly 500,000 light-years across. This unique event triggered the formation of young star clusters, each a few thousand light years across, almost 200 million years later. »

The eruption appears to have been accompanied by the emission of a jet of material that pushed the surrounding gas around the two central galaxies, creating a huge void in the cluster's intergalactic medium. Lofar shows radio waves emanating from the jet's energetic particle remnants filling the vast cavity.

For astrophysicists, based on observations from the Atacama Large Millimeter/submillimeter Array (abbreviated Alma), installed in the Atacama Desert in northern Chile, and the Gemini North telescope on the mythical Mauna Kea, the volcano, a dormant shield volcano in the United States On the island of Hawaii, the hot gas ejected from the black hole's eruption subsequently cooled.

Superclusters of stars formed by tidal forces and flows of matter

It later collapsed due to gravity, not due to the compression of a shock wave created by the black hole's eruption, but due to the tidal forces of the two galaxies. In this way they manage to explain why the super star clusters come together to form an S like pearls on a necklace.

In the same statement, Osase Omoruyi, who led the study at the Center for Astrophysics Harvard & Smithsonian (CfA), said: “We believe our evidence for this enormous burst is strong, but further observations with Chandra and Lofar would help strengthen the case confirm.” We hope to learn more about the origin of the already discovered cavity and find the expected one on the other side of the black hole. »

Astronomers have discovered one of the most powerful black hole eruptions ever recorded. This mega-explosion billions of years ago may help explain the formation of a striking pattern of star clusters around two massive galaxies that resembles “beads on a string.” This discovery was made in the SDSS J1531 system, which was observed 3.8 billion years ago. The researchers used several telescopes for this study, including NASA's Chandra X-ray Observatory and the Low Frequency Array, or Lofar, a series of radio telescopes in Europe. To get a reasonably accurate French translation, click on the white rectangle at the bottom right. English subtitles should then appear. Then click on the nut to the right of the rectangle, then click on “Subtitles” and finally “Auto-translate”. Select “French”. © NASA's Chandra X-ray Observatory

In fact, the press release also explains that Omoruyi and his colleagues only see radio waves for a cavity emanating from a single jet, but it is well known that black holes generally produce not one, but two jets in opposite directions. Although the team observed radio emissions further away from galaxies that could be remnants of a second jet, they are not associated with a cavity. The researchers therefore assume that the radio and X-ray signals from the other jet may have been weakened to such an extent that they are no longer detectable.

Roger Blandford talks to us in this video about supermassive black holes and their jets. To get a reasonably accurate French translation, click on the white rectangle at the bottom right. English subtitles should then appear. Then click on the nut to the right of the rectangle, then click on “Subtitles” and finally “Auto-translate”. Select “French”. © Quanta Magazine