Monday , January 25 2021

Astronomers observe the final stage of galaxies-fusion for the first time – Scientific Research – cnBeta.COM



According to foreign media reports, astronomers first observed the final stage of the fusion of galaxies. Through the heavy gas and dust, they saw pairs of supermass black holes closer and closer, and growing rapidly after the collision.de

In most cases, if not all, galaxies, there are supermassive black holes, whose mass is millions of millions of times the sun. For example, the Sagittarius A * in the center of the Milky Way is a very shining and dense source of radio waves, thought the nearest black hole, about 4.5 million times the size of the sun.

In the NGC 6240 galaxy, you can see that two smaller galaxies are in the final stages of the fusion. The black holes at the nucleus of the two small galaxies grow rapidly, by consuming the gas and dust that fuse the galaxies.

Some of the galaxy nuclear collisions are in the final stages of the fusion. At the top is the NGC 6240 galaxy. The image on the left is taken from the Hub gene space space of the Hubble Space Telescope. The image to the right shows the Keck Observatory's galaxy core with infrared rays. The images of the four galaxies below are translated by the Star program. "Panoramic Sky Telescope and Quick Response System" and the Keck Observatory.


Previous studies found that the concentration of galaxies can contribute to the growth of supermass black holes. The researchers suggest that black holes in the center of the collision galaxies can merge to form larger black holes.

The fusion of galaxies is likely to provide an ample opportunity for supermassive black holes to decompose stars and to eat substances. This shock releases a huge amount of radiation and is likely to be the driving force behind the square. Quadro is one of the most bright objects in the universe. However, the authors of this new paper say that the evidence supporting the supermarket black hole-based model on galaxies is very complicated. Although some studies have revealed a link between fenced vaults and galaxies, other studies have not found such associations.

A possible explanation for the apparent lack of correlation between cascades and fused galaxies is that the gas and dust around these galaxies probably probably dark black holes. Even in the early stages of the fusion, this is the case when the distance between galaxies is more than 16,000 light years. The study authors realize that computer simulations show that the size of this occlusion will be highest in the final phase of the galaxy union, where the distance between the galaxy nuclei is less than 10,000 light.

Now, researchers have observed several pairs of galaxies in the later stages of the fusion, and the supermass black holes at their center are almost always approaching. These findings will provide clues on how bigger supermassive black holes are formed.

The researchers first got 10 years of X-ray data from Neil Gehrels Swift Observatory for NASA to find out about hidden black holes. When black holes eat substances, extraordinary X-rays of these "active" black holes can be observed even if they are blocked by heavy gas and dust.

Later, the researchers watched the galaxies that equated the information of radiation therapy through data combinations of the Hubble Space Telescope and the Keck Observatory (Hawaii, United States). The first author of the paper, Michael Koss, said the Keck Observatory can make the star star more acute with a computer controlled deformable mirror by means of a technique called adaptive optics. "There is a great increase in resolution."

Coase is an astrophysicist at Eureka Scientific Technologies in Oakland, California. He said: "This is equivalent to the vision of 20/200 (similar to what we call visibility 0.1), that is to say, blindness in the legal sense, in 20/20 vision (visual power 1.0), so that we Can see people Unbelievable Galaxy details. "

In general, the researchers analyzed 96 galaxy data observed by Keck Observatory and 385 galaxies observed by the Hubble telescope. The average distance between all these galaxies and the Earth is 330 million years light, relatively close to the cosmic scale, and many galaxies are similar to the Milky Way.

The researchers found that more than 17% of these galaxies have two black holes in the center, which indicate that they are in the late stages of galaxies. These findings are consistent with the researchers' computer simulations that show that the active black holes hidden in gases and dust-rich galaxies are the cause of the fusion of many supermassive black holes.

"The fusion of galaxies can be an important way of growing black holes," said Coase. The Milky Way we enter is currently fusioning with the adjacent Andromeda Galaxy, and the supermassive black holes at the nucleus of the two galaxies may eventually hit and fuse. There are millions of light years between the two galaxies, but we (the Milky Way) move to the Andromeda galaxy at a speed of 400,000 kilometers per hour, "said Coase." In the 6 billion years, the Milky Way or the Fairy The galaxy will cease to exist, leaving only a larger galaxy. "

For galaxies hidden behind gas and dust, the clearer observations of them can come from James Webb Space Telescope. This is a infrared space telescope that is expected to be launched in 2021. Following generations of terrestrial terrestrial terrace, such as the Thirty-meter Telescope, the European Extreme Large Telescope (E-ELT) and the Gigantic Mobility Telescope, will also be available to us by active optical systems. Bring a more detailed image of the galaxy. Researchers say that James Webb Space Telescope could also measure the quality, growth and other physical characteristics of supermassive black holes closer to us.

The results of the study were released on November 7th of Nature.


Source link