The epicycles of the planets in orbit around Earth (Earth at the center). The path-line is the combined motion of the planet's orbit (deferent) around Earth and within the orbit itself (epicycle).

The meaning of EPICYCLE is a circle in which a planet moves and which has a center that is itself carried around at the same time on the circumference of a larger circle.

In the Ptolemaic system each planet revolves uniformly along a circular path (epicycle), the centre of which revolves around Earth along a larger circular path (deferent). Because one half of an …

He believed that this cyclical variation could be represented visually by mini orbits, or epicycles, revolving around larger circular orbits, or deferents. The following animation shows Mars …

Epicycles were used to explain the retrograde motion of the planets, where they appear to temporarily move backwards in the sky. The Ptolemaic system, which dominated Western …

Nov 21, 2023 · Ptolemy used epicycles to try to explain the apparent change in motion of the planets within their orbits. Planets appear to slow down, go in reverse, and then continue …

2 meanings: 1. astronomy (in the Ptolemaic system) a small circle, around which a planet was thought to revolve, whose centre.... Click for more definitions.

Examples: 1. The ancient Greeks used epicycles to explain planetary motion. 2. Ptolemy's model included epicycles to account for retrograde motion. 3. An epicycle is a smaller circle rolling …

1. a circle whose center moves around in the circumference of a larger circle: used in Ptolemaic astronomy to account for irregularities in planetary motion. 2. a circle that rolls, externally or …

Mar 18, 2025 · What is an epicycle? An epicycle is a small circle whose center moves around the circumference of a larger one. This concept, rooted in ancient astronomy, was used to explain …