The very earliest Greek theory of the structure of the universe pictured Earth at the center with the planets revolving around it at an unchanging rate in simple circles. The Greeks later revised this theory because
A) they didn't believe the theory was sufficiently beautiful to represent the eternal gods.
B) certain observations led them to the conclusion that Earth has a spherical shape.
C) they observed that the planetary motions are irregular and include such things as retrograde motion.
D) they came to believe that the sun should be at the center of things.
E) Actually, the Greeks never did abandon this theory--the theory was not altered until the time of Copernicus.

Question

Quizplus · Accepted Answer

The Greeks revised their geocentric model because they observed irregularities in planetary motions, such as retrograde motion, which could not be explained by simple circular orbits around Earth.

The Very Earliest Greek Theory of the Structure of the Universe