Friday , June 25 2021

The astronomers first observed the final stages of galaxy mergers – research – cnBeta.COM



According to foreign media for the first time astronomers have observed the final stages of merging galaxies. Through dense gas and dust, they saw a pair of supermassive black holes closer and closer, growing rapidly after the collision.Most (if not all) of the center of galaxies have supermassive black holes exist, the quality of a few hundred times a few billion times the sun. For example, in the center of the Milky Way Sagittarius A * is very bright and compact source of radio waves are believed to be where our closest supermassive black hole, its size is about 450 times greater than the Sun's mass.

The galaxy NGC 6240, you can see two small galaxies merge in the final stages. Two small galaxies located in the core of the black hole is growing rapidly, devouring gas and dust merged galaxies.

Some galaxies with & # 39 are facing cores, which is in the final stage of the merger. NGC 6240 galaxy top, left, received wide-angle camera of the Hubble Space Telescope 3, the right is taken with an infrared galactic nuclei Keck Observatory image below four galaxies program Mon-Star (the full name is literally translated as "panoramic telescope survey and rapid response system") and shooting the Keck Observatory.


Previous studies have shown that the merging galaxies can help a supermassive black hole growth. The researchers hypothesized that the collision of galaxies located in the center of the black hole may be on the & # 39 merged into a big black hole.

Merging galaxies are likely to provide opportunities for supermassive black holes swallow matter and star break. This collision produced a very large amount of radiation, and is likely to become the driving force of the quasar. Quasar with & # 39 is one of the highlights of & # 39 objects in the universe. Nevertheless, the authors of the new paper, said support evidence based on galactic merging supermassive black holes growth model with a & # 39 are very complex. Although some studies have shown a link between quasars and galaxies merge, but other studies have found no such association.

For obvious explanation is related to the possible merger of quasars and galaxies, the galaxies around them gas and dust are likely to greatly obscured by the black hole. Combined, even at early stages, when the distance between galaxies 16,000 light years, it is true. The study authors note that the computer simulation shows that the degree of this block in the final stages of galactic mergers that reach the highest distance less than 10,000 light-years from the galactic core.

Now, researchers have found that some of the galaxies in the later stages of the merger, which is located in the center of a supermassive black hole is constantly converging. These results show how much more the formation of supermassive black holes provide the key.

Researchers first 10 years of obtaining X-ray data from the National Aeronautics and Space Administration (NASA) Neil Gray Gables Swift Observatory (Neil Gehrels Swift Observatory), which filters the information about the hidden black hole. If black holes substance, even if a thick protective gas and dust may also be made "active" black holes generated by high-energy X-rays.

Then the researchers combed through Space Telescope and Keck Observatory (located in Hawaii) Hubble data, pay attention to this information corresponds to the X-ray galaxy. First author Michael Kors (Michael Koss), said Keck Observatory using "adaptive optics" technology (adaptive optics) is controlled by the deformed mirror using a computer, you can make the image of the star becomes sharper, "thereby significantly increasing the resolution."

Kos Oakland, California, Eureka Scientific Technology astrophysicist. He said: "This is the equivalent of vision from 20/200 (equal to what we call visual acuity 0.1), that blindness in the legal sense, it is the 20/20 vision (visual acuity 1.0), so that we can see this incredible detail of the galaxy. "

In general, the researchers analyzed data from the Keck Observatory observations of 96 galaxies and the Hubble Space Telescope observations of 385 galaxies. All of these galaxies and the Earth's average distance of 3.3 billion light-years on a cosmic scale is still relatively new, a lot of things like the size of the Milky Way.

The researchers found that, of which the center of a galaxy more than 17% is a black hole, which shows that they are in the later stages of galactic mergers. These data and the results of computer & # 39; computer simulations, researchers agree, the second show, hidden in gas and dust rich galaxies, black holes in active supermassive black holes on the & # 39; The combined number of reasons.

"Galactic merger can be an important way black holes grow," Kos said. We live in the Milky Way is currently in the process of merging with the neighboring Andromeda galaxy, galaxies, located two supermassive black hole in the heart, in the end, will face merges together. Now millions of light years, the distance between the two galaxies, but we (the Milky Way) is moving at a speed of 400,000 kilometers per hour towards the Andromeda galaxy, "said Kos," 60 billion years, the Milky Way, or fairies galaxy will cease to exist, leaving only the most galaxy. "

For hidden behind the dust and gas that merging galaxies, they may have a more precise monitoring of the James Webb Space Telescope NASA. This is an infrared space telescope, expected to launch in 2021. The following ground-based telescopes, such as the 30-m telescope (Thirty Meter Telescope), the European Extremely Large Telescope (European Very Large Telescope, called the E-ELT) and the Giant Magellan Telescope (Magellan Telescope Giant), and through an active optical system do more for us refined image of the galaxy. According to the researchers, the James Webb Space Telescope should be able to measure the mass of a supermassive black hole we are close distance, growth rate and other physical characteristics.

The results of this study published in «Nature» November 7 with (natural) log.


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