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CHCS Earth Science Chapter 2 (p 29-31)

theory a hypothesis that has been tested and is a workable description of a phenomenon
law a scientific theory that has become well established because it has been repeatedly confirmed by experimentation, has made many accurate predictions, or is readily accepted by the majority of scientists
geocentric theory AKA Ptolemaic Theory; has earth as at the center of the solar system
eccentric "off center" circle
retrograde motion the optical illusion that some planets slow down, stop, and back up in their orbits
epicycles small circles that were added to the geocentric theory to explain retrograde motion
deferent crystal spheres that moved around earth, each having a planet, the moon , or the sun
Created by: mrslisawatson