At present, the mass of the largest black hole in the universe discovered by human beings is 66 billion times that of the sun, and it is located in the center of the quasar TON6 18, and is away from the earth 104 billion light years.
According to Hawking's conjecture, there is a singularity in the center of a black hole, which is infinitely small in volume, infinitely large in density and infinitely large in curvature of spacetime.
There is an event horizon around the black hole. Because of the strong gravity of the black hole, the escape speed in the event horizon is greater than the speed of light. However, nothing in the universe can move faster than the speed of light, which means that black holes can devour all the matter falling into the event horizon.
Black holes are not picky eaters at all. Planets, stars and neutron stars are just food in front of black holes. Moreover, heavy black holes basically only eat and don't pull, and they will only get fatter and fatter. Only those small black holes will evaporate in a short time.
For this reason, scientists divide black holes into different grades according to their weight, that is,
Micro black hole:
This is an extremely tiny black hole, also known as quantum black hole or mini black hole. Theoretically, the lower mass limit of this black hole is Planck mass (2. 18 10-8kg). Because it is a quantum black hole, it is very different from ordinary black holes. Although micro black holes have not been found, scientists believe that they exist.
Stellar black holes:
This is what we usually call a black hole, and its mass is equivalent to that of a star. When a star is dying and the remaining core mass is more than three times the mass of the sun, it will collapse into a star-level black hole.
Medium mass black hole:
The mass is generally between 100 65438+ million times the mass of the sun. According to relevant theories, this kind of black hole is generally the level that a star-level black hole reaches after eating too much and gaining weight. Surprisingly, scientists have only found a few such black holes in the universe.
Supermassive black holes:
It is a black hole, the mass is 654.38+ million times that of the sun, and there is no upper limit on the mass. This kind of black hole is generally located in the center of the galaxy and is very important for the formation of the galaxy. There is a supermassive black hole in the center of the Milky Way. The black holes in TON 6 18 belong to supermassive black holes.
Black holes are usually the result of gravitational collapse of celestial bodies, and massive stars will become black holes after death. However, supermassive black holes like TON 6 18 are not directly formed by the collapse of stars, but grow by constantly swallowing other substances and merging with other black holes.
The greater the mass of the black hole, the stronger the gravitational field and the larger the radius of the horizon. The horizon radius of TON 6 18 black hole has reached 192 billion kilometers, which is about 27,600 times the radius of the sun (696,000 kilometers). In terms of volume, its volume is 4.2 million times that of UY, the largest known star shield in the universe.
According to scientists' speculation, quasars are supermassive black holes at the center of active galactic nuclei, and their light comes from the light released by accretion disks of these black holes. If there were no accretion disks, black holes would become invisible celestial bodies. Quasar TON 6 18 is one of the brightest objects in the universe. Its luminosity is 140 trillion times that of the sun, so we can see it at10 billion light years away.
Although quasars are much smaller than galaxies, they release thousands of times as much energy as galaxies, so they are very bright. This is because there is a supermassive black hole in the center of TON6 18. Because the black hole is very massive, it has an accretion disk about one light-year wide.
The accretion disk is formed by the matter around the black hole being attracted, torn up and moving around the black hole at high speed by the strong gravity of the black hole, which will release huge energy in the process.
Although TON 6 18 is huge, even if it is given enough time, its mass cannot grow indefinitely, and it will devour the whole galaxy at most. Because the expansion of the universe is accelerating, galaxies are not only far apart, but also far away from each other. But even so, black holes are still the scariest known existence in the universe.