The vast majority of black holes arise from the death of a star
Stars that have a mass 20 times that of our sun, at its very end, create a black hole. Existing stars produce enough “nuclear fuel” to balance gravity and internal pressure. Gravity, on the one hand, attracts matter to the surface. However, when when a star runs out of nuclear fuel, gravity will win the internal pressure and the stars will begin to quickly crumble and will eventually explode as a supernova and become a black hole.
Black holes were discovered in the 18th century
English geologist John Michell and French astronomer Pierre LaPlace are, independently of one another, the first set up the theory of black holes, and the existence of invisible stars whose gravity is so strong that nothing can escape. His theory was set at the end of the 18th century, and properly concluded that an object should have a speed more than the speed of light to escape a black hole. However, to complete the discovery, scientists had to wait until 1967, when the theory was fully proven by John Wheeler, who first began to use the term black hole.
No one can escape a black hole
After the explosion of a supernova, the star is “undercutting” the prime volume. The star gets infinite density, also known as a singularity, from which nothing can escape. In fact, the only thing that can escape from a black hole, theoretically transparently, is something that moves faster than the speed of light, but the problem is that no known object can move faster than the speed of light! Also known is the concept of the event horizon, or spherical surface that marks the border of a black hole. The event horizon can be entered, but once you enter you are already doomed.
Black holes are invisible
Given that, logically, even rays of light can not move faster than the speed of light, not even light can escape a black hole. This is precisely why black holes are invisible, or visible only to its limits, ie. Horizons of events is, recall, once you have entered into it, in this case light up no more. Therefore, the scientists observed the effect of gas, stars, planets and dust that are on the edges of black holes to reveal the existence of a single black hole. it is assumed that all galaxies, including our Milky Way, at its center has a super massive black hole.
There are three types of black holes
There are three types of black holes – super massive, mini and stellar. Super massive black holes are not only the largest black holes, but are the largest and most massive objects in the universe. They can have a mass between one hundred thousand and one billion solar masses, hence they differ greatly from stellar black holes that formed the collapse of stars, but their mass reaches only to about 33 solar masses. The smallest of all the mini black hole that is now an astronomical phenomenon that exists only in theory. Mini black holes are considered to be those black holes have a mass of less than a star.