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Explorations an Introduction to Astronomy Thomas T. Arny | ||||||||
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Chapter
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Chapter 1, Figure 30
Figure
1.30
As Venus
orbits the Sun, it undergoes a cycle of phases. The phase and its position
with respect to Sun show conclusively that Venus cannot be orbiting the Earth.
The gibbous phases Galileo observed occur for the heliocentric model but cannot
happen in the Earth-centered Ptolemaic model.
