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D's presentation --- Black Holes

(2007-03-27 21:28:43) 下一个

BLACK HOLES

Black holes. A word that sparks imagination to life. When mentioned we think of a swirling vortex in space sucking everything up in its path, but can such a thing exist?

 

In 1784, John Michell a geologist tried proving that black holes exist. He failed, but inspired other astronomers to try proving black holes exist. In 1915 Albert Einstein proved that light was affected by gravity, which helped Karl Schwarzschild give a equation showing that black holes can theoretically exist. In 1967 Stephen Hawking and Roger Penrose proved that black holes can exist. Today we have seen black holes.

 

            Most people think black holes are vortexes in space. They aren’t. Black holes are invisible, so how do we see them? They give off radiation. The radiation is created when matter or energy collide and burn. This also causes the black hole to evaporate. You can only see black holes using x-rays.

 

            Black holes are created by stars, but not just any star. Only stars four times larger than our sun can collapse into black holes. Other things can be created from a collapsing star. Stars four times smaller than our sun usually collapse into white dwarfs, which are almost four times brighter than our sun. Stars as large as our sun and smaller than four times larger than our sun can collapse into neutron stars, which have high gravity.

 

            In space things that are small and heavy have high gravity. The smaller and the heavier the more gravity. Black holes are one of those things. The gravitation field of a black hole is called the event horizon. Every thing outside this boundary can orbit without moving closer towards the black hole. Once something has entered into black hole everything outside cannot see anything of what happens in the interior. The event horizon is the edge of no return.

 

            Black holes gravity are so powerful that it affects time. Things in the gravitational field experience time slowing down, while near the event horizon time speeds up

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     One black hole is in the center of a galaxy close to ours, how do we know? Sometimes energy and matter get spewed out the center of black hole in two directions opposite of each other. This happens when a black hole can’t absorb the energy quickly, but most black holes are discovered by x-rays.

 

            When black holes were discovered and before. Black holes inspired fiction writers and movies directors to write something on worm holes and vortexes, which all resemble a black hole. Today writers and directors are still using the black holes to make movies and books.

 

            Some mysteries might never be revealed.  Black holes are one of those things. What lies in a black hole and what lies on the other side? Mysteries like these will continue to drive scientists and astronomers farther to discover more about space, but the we find out the more mysteries we might reveal.

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