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How old is the universe?
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Most astronomers believe that the universe began about 15,000 million years ago with a gigantic explosion, which they call the Big Bang. Earth was formed 4,500 million years ago. | | Matter formed in the Big Bang collected in clouds. The clouds collapsed inward and formed galaxies. |
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Previous:
Back
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Book:
1001
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Section:
Space
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Chapter:
The Universe
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