What did Galileo's observation of the phases of Venus confirm about its motion?

Answer

That Venus must orbit the Sun.

Seeing Venus exhibit a full set of phases proved it must orbit the Sun, placing the Earth outside of Venus's orbit, a finding inconsistent with the Ptolemaic model.

What did Galileo's observation of the phases of Venus confirm about its motion?

#Videos

How We Figured Out That Earth Goes Around the Sun - YouTube

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