On which of these assumptions do Ptolemy and Copernicus agree?
A)The Earth must be the center of all motion in the Cosmos.
B)All orbits must be perfect circles.
C)The Sun was bigger than the Earth.
D)Venus must always stay between us and the Sun.
E)The Sun must orbit us, but the planets do orbit the Sun.

Question

Quizplus · Accepted Answer

Ptolemy and Copernicus both believed in the assumption that all orbits must be perfect circles. However, they did not agree on the other assumptions listed. Ptolemy believed that the Earth must be the center of all motion in the Cosmos, while Copernicus proposed that the Sun was the center of the universe with the planets orbiting around it in elliptical orbits. Ptolemy also believed that Venus must always stay between us and the Sun, while Copernicus did not have this assumption. Lastly, Copernicus believed that the Sun must orbit us, while Ptolemy believed in a geocentric model where the Earth is stationary and the other celestial bodies orbit around it. Both Ptolemy and Copernicus assumed that all orbits must be perfect circles.

On Which of These Assumptions Do Ptolemy and Copernicus Agree