Speaking in a general sense, in the universeThere are two kinds of black holes. The first is the black holes of stellar mass and relatively small size. They are born as a result of the death of old stars. By attracting with the help of gravity and absorbing gas, other stars and other matter of the cosmos, they turn into supermassive black holes (the second kind) - significantly larger and more massive objects. Scientists believe that supermassive black holes first appeared in the universe. But how could this happen if for a long time there were no stars in the early Universe from which they could be born?
What do supermassive black holes look like?
Take a look at the picture above. It shows one of the largest (supermassive) black holes in our Universe. See how the dimensions of Neptune's orbits (the farthest planet in the solar system) and the Earth's orbits look on its background. In astronomy, distances are considered to be light years, months, weeks, days, hours and minutes. In short, these are all distances that light travels in one earthly year (months, weeks, and so on).
Its mass is 14% of the mass of the entire galaxy in which it is located. These are billions of solar masses.
To gain millions and billionsSun masses, which can boast of many similar supermassive black holes, can take a very long time. However, there were already black holes that appeared surprisingly early. Such objects are known that appeared after 800 and even 690 million years after the Big Bang, when there were very few stars in the Universe.
See also: 10 new amazing discoveries associated with black holes
How did the first black holes appear in the universe?
It is difficult to understand how they could be formed andgrow in such a short time. This riddle remains one of the most interesting in modern astronomy. And for its solution was proposed many different hypotheses. For example, one of them.
However, scientists from the University of Western Ontariobelieve that the first black holes could appear as a result of a “direct collapse” - not from stars, but from dense clusters of gas in the centers of the first galaxies that were in the process of their formation. Warming up and intensely radiating radiation, such clusters blocked the appearance of young stars in an increasingly vast space of the cosmos.
The presence of a huge amount of free matter(gas and dust) allowed these clusters to very quickly gain critical mass and density. After that, they collapsed, leaving behind black holes weighing tens and hundreds of thousands of suns.
See also: Can black holes destroy the universe?
Gravity can gas just beforeof the moment until matter begins to accumulate around the black hole, forming a hot disk that emits intense radiation and repels the incoming gas, thus stopping the growth of the black hole. This is called the Eddington limit.
Scientists from the University of Western OntarioThey proposed a mathematical model of this process, showing that it could really develop very quickly. The researchers explain that the radiation of newborn stars and other holes soon reached a critical limit. As a result, the “direct collapse” of new supermassive holes has become impossible.
Black holes still keep a lot of secrets, the solution of which, according to scientists, may contain answers about how the Universe in which we live appeared and developed.
Read also: The first ever black hole photo has been published
Subscribe to our Yandex. Dzen to keep abreast of the latest developments from the world of science and technology.