A Closed Universe
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The Big Crunch

If there is enough matter in the Universe eventually gravitational forces will stop its expansion. When this happens gravity will cause the universe to reverse its direction and begin to collapse under its own weight. This phase of the Universe's life is known as the Big Crunch.

Eventually all of the matter in the Universe will collapse into a super dense state and possibly even collapse into an unimaginably massive black hole. Some theorize that the Universe could collapse into the same singular state that it began as and then blow up in another Big Bang. In this way the Universe would last forever but would continually go through these phases of expansion and contraction, Big Bang and Big Crunch and so on...

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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