Black Holes Facts
Learn amazing information about black holes by reading black holes facts. Black holes are concentrated areas of space that have extremely strong gravitational pulls. The infinite darkness, strength, birth and mysteries of black holes fascinates the public.
- Most common black holes are created by the death of a star. Stars with masses 20 times larger than the Sun will make a black hole at death. A living star will produce enough nuclear fuel to balance gravity and pressure, but when the star dies gravity will compress material in the core. This causes the star to collapse into itself, explode as a supernova and become a black hole.
- No object can escape black holes. After the supernova explosion, the dead star compacts to zero volume. The dead star is given infinite density, also known as singularity, that no object can escape from. Only an object faster than the speed of light may escape a black hole. No object can reach a velocity greater than the speed of light.
- Black holes are invisible. Since even the speed of light can not escape the gravitational pull of black holes, they are invisible and very difficult to find. Scientists observe the effects of gas, planets, stars and dust surrounding areas in space to discover black holes. Heat and motion of gas and dust orbiting around an event horizon, which is the edge of the black hole, is a sign of the presence of a black hole.
- There are three types of black holes. Three types of black holes exist: supermassive, miniature and stellar black holes. Supermassive black holes are the largest black hole; they capture orbiting stars in the center of most galaxies. Stellar black holes are much smaller than supermassive black holes, but they are larger than miniature black holes. For example, a supermassive black hole may be 4,210,000 solar masses while a stellar black hole is just 15 solar masses.
- John Michell and Pierre LaPlace theorized black holes. In the 1790s, John Michell and Pierre LaPlace suggested the existence of an "invisible star." The mass and size of "invisible stars" were calculated by LaPlace and Michell. They theorized that an object would need a velocity greater than the speed of light to escape from the event horizon of these unseen stars. Invisible stars, commonly known as black holes, were fully discovered by John Wheeler in 1967.