Even though black holes are very hard to detect, scientists from NASA claim that the milky way alone has around 100 million to a billion black holes. There is infact one scientifically proven black hole right in the middle of the milky way, named Sagittarius A*. The giant is 26,000 light years away from us and 44 million km in diameter.
Just like humans not all black holes are the same, they differ in the way they form and act. Namely there are three types of black holes, the supermassive, stellar-mass, intermediate-mass. The supermassive forms when an existing black hole mergers, the intermediate one forms when multiple stellar merges with one another, and finally the stellar forms when a star dies.
You may have heard from a lot of people that one day our sun is going to turn into a black hole, well i have good news for you..... It cannot. In order for a black hole to form, a star the mass of 10-20 times our sun must die, with the smallest black hole measuring three times the mass of our sun.
Although only partially true, Albert Einstein's theory of relativity predicted the existence of black holes in 1916. But only in 1967 the term "black hole" was coined by John wheeler. Einstein's theory made it possible for Karl Schwarzchild to discover a non light escaping volume - black hole.
The closest discovered black hole to earth is about 1500 lightyears away and is named the "unicorn". The unicorn is one of the smallest known black hole, it is only about three times the mass of the sun. These unique characteristics of the astronomical object has made scientists to name it the unicorn.
There are black holes that can swallow entire planets and then there are black holes that can swallow a galaxy. The biggest ever black hole found lies 10.37 billion light years away from earth and has 66 billion solar masses. It exists at the center of the quasar Ton 618. In comparison the quasar is about two times the size of milky way.
A black hole is slow strong that it sucks in anything, literally anything including light. Due to this insane amount of gravity and curvature of spacetime, it takes a lightbeam more time to travel in a black hole. But to a normal human; light should travel at 300,000 km/s, and since light is slower in blackhole it appears as time slowed down due to the time/distance relationship of speed.
Event though the theory of black hole and black hole itself has been discovered a long time ago, the first photo of the supergiant would only be captured in 2019. More than 50 million light years away, with the mass equivalent to 6.5 billion suns this black hole could devour anything that dares to go inside it's event horizon.
As all things, even a black hole doesn't last forever. According to Stephen Hawking, as a black hole absorbs stuff it must lose energy in the process and gradually disappear. Even though there's not a specific amount of time in which all black holes disappear, it depends on how big the black hole is.
Black holes are formed due to the explosion of stars when they run out of energy, this newly formed mass has a gravity so high that it sucks everything into it. If a black hole were to replace our sun with the same mass, then nothing would change and earth will still be orbiting around it, therefore bigger the black hole higher the gravity.
