<Tr> <Td> Interior planets </Td> <Td> Average greatest elongations of 23 ° (Mercury) and 46 ° (Venus) </Td> <Td> Size of epicycles set by these angles, proportional to distances </Td> </Tr> <Tr> <Td> Interior planets </Td> <Td> Limited to movement near the Sun </Td> <Td> Center their deferent centers along the Sun--Earth line </Td> </Tr> <Tr> <Td> Exterior planets </Td> <Td> Retrograde only at opposition, when brightest </Td> <Td> Radii of epicycles aligned to Sun--Earth line </Td> </Tr> <P> The geocentric model was eventually replaced by the heliocentric model . The earliest heliocentric model, Copernican heliocentrism, could remove Ptolemy's epicycles because the retrograde motion could be seen to be the result of the combination of Earth and planet movement and speeds . Copernicus felt strongly that equants were a violation of Aristotelian purity, and proved that replacement of the equant with a pair of new epicycles was entirely equivalent . Astronomers often continued using the equants instead of the epicycles because the former was easier to calculate, and gave the same result . </P>

Who supported the geocentric model of the solar system