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Ptolemaic system science definition
The astronomical system of Ptolemy, in which Earth is at the center of the universe and all celestial bodies revolve around it. The Sun, Moon, and planets revolve at different levels in circular orbits, and the stars lie in fixed locations on a sphere that revolves beyond these orbits. See more at epicycle.
Ptolemaic system
Ptolemy believed that Earth was at the center of the universe and that the Sun and planets orbited Earth (with the planets also moving in smaller circles called epicycles). In this system, the centers of Mercury's and Venus's epicycles always lie on the line shown in the diagram between the Earth and the Sun.
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