Aristotle
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Aristotle promoted an earth-centered, or geocentric, model of the solar system. His model didn't explain why some planets appear to reverse direction occasionally. This backward motion is called Retrograde Motion.
Ptolemy
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Claudius Ptolemy proposed a model of the universe in which each planet had two motions. One motion was the revolution of the planets around the earth. As the planets revolved, they also moved in a series of small circles that Ptolemy called epicycles.