As you know, a # black hole is not really a hole. Its density is extremely high, its gravity is extremely strong, and it is so large that even light cannot escape. Without light, humans cannot observe black holes.
Today, let's learn together about the 10 knowledge you must know about black holes.
- The "most" black hole
It is known that the closest black hole to Earth is called "Unicorn", which is only 1500 light-years away from us and is currently the smallest black hole discovered, only three times the weight of the Sun;
The largest black hole in terms of mass is TON 618, which is approximately 66 billion times that of the Sun;
The farthest black hole from Earth is located at the center of the galaxy QSO J0313-1806, approximately 13 billion light-years away from Earth.
- Spaghettization
This is an astronomical term used to describe the transformation of a celestial body into noodles when it encounters a black hole and is stretched by gravity.
But if scientists have been to Xinjiang, they would definitely think it would be better to describe this phenomenon as "stretching".
- The magic of love revolves in circles
All black holes are rotating, and a black hole named GRS 1915+105 is currently known to be the fastest spinning black hole, rotating 1000 times per second.
- When black holes replace the sun
If a black hole with a mass equivalent to the sun replaces the sun, will the solar system be engulfed?
The answer is no. Except for becoming dark and cold, all celestial bodies in the solar system will maintain their current orbits.
- Formation
Black holes are usually products of the death of supermassive stars, which may be born directly after a supernova explosion, or they may be born from the fusion of two neutron stars.
- Are there many black holes?
Black holes are not uncommon, and scientists estimate that the Milky Way alone has at least 100 million black holes.
Most black holes only float quietly and do not devour celestial bodies, and they are too far away from Earth for humans to find them.
- A hiccup black hole
Previously, people believed that black holes belonged to Pixiu, but in October 2022, scientists observed a black hole spewing out some matter at half the speed of light.
And three years ago, it just swallowed a star. Researchers say this phenomenon is like a black hole burping.
- Particle accelerator
Some supermassive black holes located at the center of galaxies can accelerate ejected particles to near the speed of light.
- Hand Rubbing Black Hole
If you can compress an object to its Schwarzschild radius, you can rub a black hole by hand. The Schwarzschild radius of the Sun is 3 kilometers, while the Schwarzschild radius of the Earth is 9 millimeters.
But the sun and the earth cannot become black holes. To become a stable black hole, at least three times the mass of the sun is required, and the lower limit of this mass is called the Oppenheimer limit.
- Event Horizon
The following is a picture of a black hole, with the bright outer part called an accretion disk and the black middle part serving as its event horizon. Any object that enters the event horizon cannot escape, including light.
The radius of the event horizon is the Schwarzschild radius of a black hole, which is hidden within the event horizon and its size can never be known by humans, hence it is called a singularity.