Astronomers argued that the heliocentric model of the Solar System was simpler than the geocentric model, based on
A) the observation that the planets do not move relative to the background stars.
B) the fact that the Moon orbits Earth.
C) the fact that the Sun is more massive than Earth.
D) the observed retrograde motions of the planets.
E) the observed timing of lunar and solar eclipses.

Question

Quizplus · Accepted Answer

The heliocentric model naturally explains the retrograde motion of planets as an apparent effect due to the relative positions and motions of Earth and the other planets, making it simpler than the geocentric model which required complex epicycles.

Astronomers Argued That the Heliocentric Model of the Solar System