On the outskirts of the tiny galaxies suddenly discovered supermassive black holes

Only recently, astronomers learned that dwarf galaxies also occur supermassive black holes. Scientists do not have time to get used to this fact, as the universe has presented a new surprise. It turned out that many of the “heavyweights” are not in the center of their star systems.

the Discovery is described in a scientific paper published in the Astrophysical Journal by a group led Amy Raines (Amy Reines) from the University of Montana.

In the centers of large galaxies with hundreds of billions of stars, usually hidden supermassive black holes. (Recall that a black hole is called a supermassive, if its mass is not less than a million solar.) And what of the dwarf galaxy in which only a few billion suns?

until recently it was believed that such animals are not found. But in 2011, Raines and co-authors published an article about the opening of the first supermassive black hole at the center of the dwarf star system.

Astronomers have launched a systematic search for dwarf galaxies with supermassive black holes discover about hundreds of such systems.

“once I started to specifically look for these objects, I found a whole bunch,” says Raines.

Amy Raines made a second discovery overturning ideas about dwarf galaxies.Photo by Adrian Sanchez-Gonzalez/MSU.

Part of this work was a new study. The authors selected 111 galaxies within a billion light years. In each system the total mass of stars does not exceed three billion suns. Astronomers observe these objects with a system of radio telescopes and the VLA. Black holes are identifiable by the radiation falling on them of substance.

the Authors have selected 13 systems almost certainly contains a supermassive black hole. And then the scientists were in for a surprise: in most of these galaxies “monster” lived not in the center.

“All the black holes discovered by me earlier, were in the centers of galactic. These wandered on the outskirts. I was amazed when I saw it,” admits Raines.

Note that last year, another group of astronomers published the interesting results of computer modeling. The experts then was that 50% chance of a supermassive black hole in dwarf galaxy will not be in the center, and thousands of light years from it. Now, observations have confirmed this bold conclusion.

“Fleeing from the center” may be the result of the gravitational effect of neighboring star systems, scientists suggest. In addition, the black hole may not be native to this galaxy, and get her in a collision with a neighbor. (It is also possible that a black hole just tired of traffic jams and dirty air in the center and moved to a quieter area).

In connection with the current results, the experts propose to change the approach to the search for supermassive black holes in small stellar systems.

“We need to expand the search scope to cover the whole galaxy, not just its nucleus, where, as we previously expected, and could only be a black hole,” says Raines.

By the way, before “News.Science” (nauka.vesti.ru) wrote about black holes, ready to face, and that a supermassive black hole at the center of our galaxy may not be the only one.

Text: To.Science