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Anaximander's model of the universe tried to explain how the moon changes phases and why we can see the stars when it's dark.
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Aristotle's model of the universe showed the planets and sun rotating around the earth with the stars in fixed positions, but it did not explain how mercury and mars retrograded, as it was not accurate.
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Ptolemy solved the problem with Aristotle's model by having the planets orbit in small circles while orbiting around the earth. This model was used for a long time.
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Copernicus was a polish astronomer who first suggested a heliocentric model, a model in which the sun is in the middle.
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