In modern general relativity, black hole is a kind of celestial body existing in space.
The gravity of the black hole is so strong that it absorbs everything, making the escape speed in the event horizon faster than the speed of light, so that even light can’t escape the phagocytosis of the black hole.
In our understanding, the darkest object in the universe is black hole, which is even darker than the black dwarf star after the death of a star. Black hole does not reflect light, but endlessly absorbs it.
In theory, this should be the case, but it is not the case. In many photos we see, we will find that black holes are very bright.
Even if you ask any astrophysicist, they will tell you that a black hole is one of the brightest objects in the universe.
This is contrary to our understanding. Why?
Why are black holes so bright?
In fact, these bright lights are not emitted through the black hole itself. As mentioned earlier, because the black hole has a great gravity, even light will not pass, so it will absorb any kind of celestial body or matter in the universe.
For example, when a black hole absorbs a nearby star, it will first absorb the gas attached to the outer ring of the star, and the atoms that make up the gas will be pulled and move violently, producing a large number of positive ions and negative electrons. Charged particles will produce turbulent magnetic fields, thus the black hole will form an accretion disk around it.
What is an accretion disk?
Accretion disk is a kind of plate-shaped structure, which often moves around the star, is composed of a kind of dispersed material, and revolves around the central body (including stars, black holes, white dwarfs, etc.).
After absorbing the gas, the black hole will continue to absorb the star through its strong gravity, smashing the star into basic particles.
At the same time, the process also releases a lot of energy, which, together with the shredded particles, will form a bright accretion disk around the black hole.
Temperatures can reach hundreds of billions of degrees Celsius, which is why invisible black holes appear as bright clusters of light.
Black holes in the center of the galaxy
I wonder if you have noticed that the center of the galaxy is very bright. Do you know why?
In the center of the galaxy, there are many stars gathered together.
If our solar system were located in the center of the galaxy, we would be exposed to 100 times the radiation, and there would be no life on earth
There is also a silent supermassive black hole in the center of the galaxy, named a * Sagittarius, which has a mass about 4 million times that of the sun.
This black hole is very important to the galaxy, because it maintains the evolution of the whole galaxy and the life of celestial bodies with its powerful control.
It can be said that without the existence of Sagittarius A *, the galaxy would be torn apart.
Why is this black hole silent?
Scientists observed it and found that the hot gas near Sagittarius A * was moving outward and gradually cooling.
However, it does not die out, it is still active, and sometimes it becomes extremely bright.
At present, scientists are not sure whether these flares are the result of hot gas falling into the black hole, or shock wave passing through the gas, or the bow breaking of magnetic material.
See here, don’t you think the black hole subverts your cognition!
The universe is very mysterious. Human beings are gradually understanding it through the power of science and technology. Maybe in the near future, we will find more incredible things in the universe, let’s wait and see!
What do you think of that? Welcome to comment area.