Black Holes
The Depths of the Skies
What are black holes exactly?
Black holes as many may think were just a part of the universe and they were always there and always will be, but that is very untrue. In fact black holes were all once stars and when the star dies it forms black holes. In depth the stars stay as stars by burning, as we often see in the night sky; the stars are pushing outwards as the force of gravity that exists to pull it inwards. When the star no longer has fuel or gas to burn, the star starts to shrink until the star explodes violently, then the gravity of the star creates a black hole.
What they can do?
The black holes absorb all objects into it, in the proces the object slowly approaches the black hole, as the object approaches the black hole's event horizon the object instantaneously start getting pulled into the black hole, but the object is still not completely inside of the black hole but it creates the illusion that the black hole is stretching out the object. Black holes bend light and is impermeable to see through.
How are black holes formed?
Stage 1
This is the first stage of a "black hole" where is is still a sun, but a very bright star that is large enough to shine a bright blue which has a very large mass.
Stage 2
This is the stage where the star no longer has enough fuel to burn and expand with an outward force against gravity and expands until gravity overcomes the star.
Stage 3
The gravity of the star has overcome the outwards energy of the star therefore creating a black hole.
Discovery of the black hole
The first recorded information of black holes were first stated by a geologist of the name of John Michell in a letter he wrote to Henry Cavendish in 1783:
"If the semi-diameter of a sphere of the same density as the Sun were to exceed that of the Sun in the proportion of 500 to 1, a body falling from an infinite height towards it would have acquired at its surface greater velocity than that of light, and consequently supposing light to be attracted by the same force in proportion to its vis inertiae, with other bodies, all light emitted from such a body would be made to return towards it by its own proper gravity."- John Michell
"If the semi-diameter of a sphere of the same density as the Sun were to exceed that of the Sun in the proportion of 500 to 1, a body falling from an infinite height towards it would have acquired at its surface greater velocity than that of light, and consequently supposing light to be attracted by the same force in proportion to its vis inertiae, with other bodies, all light emitted from such a body would be made to return towards it by its own proper gravity."- John Michell
The theory of general relativity, which was made by Einstein was used by Karl Schwarzchild that was used to explain gravitational fields in point mass which lead to the theory that black holes exist.
Citations and sources of information
Horizon: Black Holes (BBC)