Crash Course Astronomy

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

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.

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

13m 9s

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.

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