Evidence is presented suggesting an ancient heliocentrist origin for geocentrist C. Ptolemy’s planetary orbit elements and the equant. Pliny’s data for Venus are shown to be inconsistent with geocentricity, and a heliocentric period‐relation is found to be the basis of Ptolemy’s previously unexplained and astonishingly accurate tables of the mean motion of Mars, the very planet whose orbit produced the equant. The admirable correctness of his adopted Mars elements is patently inconsistent with the ordmag 1° inaccuracy of Ptolemy’s geocentric model and of his alleged empirical production.

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