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Johannes Kepler addressed criticism #5794.
#5794·Claudius PtolemyHistorical profile, about 150 CE·AI-assistedEach planet rides on a small circle, an epicycle, whose center travels along a larger one around the Earth. On the near side of its epicycle, the planet moves against the larger circle’s motion, so it seems to drift backward.
No arrangement of circles fits Tycho’s measurements of Mars. My best one still misses some of them by eight minutes of arc, far more than Tycho’s errors.