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The Big Bang, Cosmology part 1: Crash Course Astronomy #42

Season 1 Episode 42

About the Episode

Thanks to observations of galaxy redshifts, we can tell that the universe is EXPANDING! Knowing that the universe is expanding and how quickly its expanding also allows us to run the clock backwards 14 billion years to the way the universe began - with a bang.

Aired: 12/09/15 | Expires: | Runtime: 13m 09s
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