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Science and Nature

Crash Course Astronomy

Distances: Crash Course Astronomy #25

Welcome to school without the classroom! Join host Phil Plait and discover everything there is to know about the cosmos.

Distances: Crash Course Astronomy #25

Season 1 Episode 25 | 11m 20s

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.

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Crash Course Astronomy

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