Black Holes
...nto the state of singularity. Becoming a part of the black hole. It’s believed black holes form when stars or other unknown massive objects in space collapse under their own gravity. Nuclear fusion in the core of a star generates electromagnetic radiation. This radiation produces an outward pressure that pushes against the inward pull of gravity caused by the star’s mass. The opposing forces create a balance that keeps the star from collapsing into higher densities. Two new types of pressure arise and their densities are a million and a million billion times the density of water. Once the nuclear fuel runs out when a star is near the end of its life, there is no longer any radiation to push outward. Gravity then causes the stars core to collapse. This state is referred to as singularity. The star’s mass and the left over outward pressure determines how far the star will collapse into higher density and if it will become a black hole or not. If the star is not massive enough or if it is not compressible enough it may turn into a white dwarf or a neuron star. There are two types of black holes which can be formed. They are known as the Schwarzschild and Kerr black holes after those who discovered them. A Schwarzschild black hole does not rotate and is spherically symmetric. A Kerr black hole is a rotating spherical black hole. Both of these types of black holes did not originate this way. When a black hole forms the dynamics of the process often produce disturbances in spacetime that lead to gravitational waves. When black holes emit gravitational waves they lose energy and eventually become stationary. After a black hole forms it can have no electric charge. If it had an electric charge it would quickly attract objects of the opposite charge. Aside from a black hole’s mass and momentum there are no other characteristics black holes can exhibit. The radius of the horizon of a schwarzschild black hole is dependant on the mass of the body. It is 2.95 times the mass of the body in solar units (mass of the body divided by the mass of the sun). If the body of the black hole is electrically charged or rotating different characteristics come about. A black hole is black and appears to be invisible when blending in with space because the gravitational pull exerted by the black hole is so great not even light can escape. The light has seemingly been hidden from the visible universe. If no light escapes it’s impossible to see black hole or take a picture of one. The only known object whose gravitational pull is so great that light can’t even escape is a black hole. The way we know black holes exist is before gravity causes them to collapse it takes an object with great mass compressed into a small area to produce a gravitational field strong enough to contain light. If you could keep the suns mass, but compress it into an area only six kilometers in diameter the sun would now be a black hole. There is no size limit to black holes. They have as much mass or as little mass as you can imagine. The gravitational force of an object increases as the volume of an object becomes less but the mass stays the same. As long as it is compressed to a high enough density a black hole is formed. The first convincing evidence of the existence of black holes came from evidence provided by the Hubble Space Telescope in 1994. Astronomers measured the acceleration of gases around the center of galaxy M 87. They concluded an object that would be able to accelerate gases at that speed must have a mass of 2.5 billion to 3.5 billion solar masses. In 1995 another prospective black hole was found at the center of galaxy NGC 4258 using the Very Long Baseline Array (VBLA), which is a large amount of radio telescopes covering a long area. The Hubbl...