KnowraDeferent and epicycleLinked fromLinked fromThe 13 pages that link to Deferent and epicycle, each with the reason it gives.All 13Broader topic 8Related 5PtolemyBroader topic: Ptolemy used these circles to reproduce planets’ changing apparent speeds and retrograde loops.AlmagestBroader topic: These circles represent planetary paths within Ptolemy’s computational system.Ptolemaic systemBroader topic: Their combined motions form the system’s main device for matching planetary paths.Retrograde motionBroader topic: This device generated apparent reversals in geocentric models before heliocentrism explained them through relative motion.Ancient Greek astronomyBroader topic: This construction reproduced planetary loops within a broadly Earth-centered model.GeocentrismBroader topic: These circles reproduced retrograde motion without moving Earth.Claudius PtolemyBroader topic: This nested-circle construction is the signature device of Ptolemy’s planetary models.Copernican systemBroader topic: Copernicus retained this device to reproduce planetary positions while changing the system’s center.