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Aristotle taught that all heavenly bodies traveled at constant speed in the path of a circle whose center was exactly the Earth.
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geocentric model of Aristotle as shown in a book written by a Christian in 16th century Portugal.
[To be more precise, the high resolution version of this illustration actually shows the modification made later to Aristotle’s diagram to change the relative sequences of the distances to Mercury, Venus and the sun.]
(Center portion of page is blank because it would not be visible when page is sewn into binding of a book)
Since the Earth is in the same plane as these circles, these motions appear to an observer on the Earth to be linear motion at a non-uniform and sometimes retrograde velocity.
Aristotle in the 4th century BC borrowed his model from Plato. Aristotle stated that heavenly bodies are made of an exalted substance whose natural state is to move in circles at a steady speed, so therefore all paths in astronomy are circular paths of constant speed.
The teachings of Aristotle are:
1. The 7 heavenly bodies travel in circular paths around the Earth, with these paths being in the same flat plane. https://www.facebook.com/photo.php?fbid=1363933850289558&id=100000188682277&set=gm.1183310915036377%3Atl_objid.1183310915036377&__tn__=E
Aristotle borrowed from Plato that the heavenly bodies in sequence of their distance from the Earth were the moon, sun, Venus, Mercury, Mars, Jupiter and Saturn. [This agrees with a literal translation of the Quran.]
Later, Ptolemy changed the sequence to be the moon, Mercury, Venus, the sun, Mars, Jupiter, and Saturn.
2. The paths are perfect circles with the Earth exactly at the center of these circles.
[A literal translation of the Quran implies that Allah makes things perfect.]
3. The stars travel in perfectly circular paths around the Earth at a distance from the Earth that is slightly greater than the distance of Saturn from the Earth. [This contradicts a literal translation of the Quran, which clearly states that the stars are closer to the Earth than the moon, sun and planets are.]
4. The Earth does not rotate. [This agrees with what is implied in a literal translation of the Quran.]
5. The moon creates its own light and is not merely reflecting the light of the sun. [This agrees with a literal translation of the Quran that clearly states that the moon is a fire.]
6. The heavenly bodies travel at constant speed. [This contradicts a literal translation of the Quran that implies the moon begins to catch up to the sun, but then becomes dim and slows down.]
Image by cartographer Bartolomeu Velho, 1568, via Wikimedia Commons.