introduction
a Giant black hole He is Astrophysicsa Black hole for whom Mass Almost one million to one billion Of solar masses. It is the most common type of black hole particlelong before Primordial black hole (still virtual), and Stellar black hole And The black hole mediator.
Supermassive black holes in the centers of galaxies
Today, a lot Notes He showed that almost all large galaxies contain a supermassive black hole at their center. This is the case for us, for example galaxythere milky way. The most important observations about the existence of such a black hole on our planet galaxy It is the orbital movement of the stars closest to the center of the galaxy, in the region called Sagittarius A*. Tracing the tracks made it possible to directly measure the mass of the central black hole: 2.6±0.2 million Of solar masses. In 2002, astronomers tracked the star S2 in Sagittarius A*, and were able to show its closest approach. 17 light hours From the central black hole.
an exercise
there Formation of black holes The issue of supermassive mass remains a subject of vigorous debate since it is certainly done on large scales of organisms timeTo compare with the formation of a black hole excellent During the explosion A Supernovaproduced by A a star particlelike Wolf Wright's star.
Obviously, the simplest hypothesis for the formation of supermassive black holes is that they start with a stellar black hole which will then accrete Theme Over billions of years. However, this hypothesis has many drawbacks, including the need for a very large amount density of stars to constantly feed the black hole. But above all, observations showed the existence of supermassive black holes with very large shifts towards redThat is, at the beginning of the evolution of the universe. Therefore, these black holes simply did not have enough time to form Accumulation Who are the stars. It is possible that the formation of such black holes occurred very rapidly at the beginning of the modern era life Universe.
the Satellites Chandra It also made it possible to observe the center of the galaxy NGC 6240 Two supermassive black holes in It rotates in orbit Monday around from the last.
Properties
Compared to a stellar black hole, the density middle A supermassive black hole can be very faint (sometimes fainter than water). This is explained by the fact that Schwarzschild radius From the black hole grows in association with the mass, which Caused by The density decreases accordingly Square Mass: As the size of a black hole increases, its average density decreases, even if its mass increases infinitely. Another notable fact is that tidal forces are negligible alive For the event horizon of the supermassive black hole, because Uniqueness Centripetal force is very far from that. Which means that an explorer approaching a supermassive black hole would not feel anything in particular when crossing the horizon.
Examples
- 4c +37.11 In the constellation From Perseus
- Abell 400 in the constellation whale
- HE0450-2958 In a constellation chisel
- OJ 287 in the constellation cancer
- NGC4261 In the constellation Virgo
- Q0906+6930 in the constellation Big Bear
- Sagittarius A & A* in the constellation Sagittarius
