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Discussion of the Ptolemaic Model of the Solar System

Was the Ptolemaic model geo- or heliocentric? Explain. How did Ptolemy and others before him account for retrograde motion (epicycle and deferent)? What is the most basic explanation for why this complicated theory could not possibly be correct?

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The Ptolemaic model was geocentric, with the Earth in the center of the solar system and all other known planetary bodies orbiting around it, including the Sun.

See: http://solarsystem.colorado.edu/images/Ptolemaic.gif

Normally, planets move from west to east against the "fixed" background of stars. Retrograde motion is characteristic of planets. It is a backwards motion against the background of stars, movement from east to west. To account for retrograde motion in his model, Ptolemy created the idea of epicycles. Epicycles were a circular orbit of a planet around a fixed ...

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In this solution, I discuss the Ptolemaic Model of the Solar System, how he accounted for retrograde motion, as well as its faults and the reasoning behind them.

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