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Crash Course Astronomy

Distances: Crash Course Astronomy #25

Video duration: 11:20

How do astronomers make sense out of the vastness of space? How do they study things so far away? Today Phil talks about distances, going back to early astronomy. Ancient Greeks were able to find the size of the Earth, and from that the distance to and the sizes of the Moon and Sun.

Episodes of Crash Course Astronomy45

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