In the geocentric model of the solar system developed by Ptolemy, the planets move
A) with varying speeds in elliptical orbits around Earth.
B) at constant speeds in circular orbits around Earth.
C) in circular epicycles around the Sun, while the Sun moves in a circular orbit around Earth.
D) in circular epicycles, while the centers of the epicycles move in circular orbits around Earth.

Question

Quizplus · Accepted Answer

Ptolemy's geocentric model posited that planets move in small circles called epicycles, with the centers of these epicycles themselves moving along larger circles (deferents) around the Earth. This complex system was designed to account for the apparent retrograde motion of the planets.

In the Geocentric Model of the Solar System Developed by Ptolemy