Which describes one way that Aristarchus's explanation of the movement of objects in the sky was different from other scientists' earlier explanations?

Question

He discovered Venus’s phases.
He argued that Earth rotates on its axis.
He explained the concept of retrograde motion.
He described the epicycles of the planets in the sky.

Answer 1

Aristarchus's explanation of the movement of objects in the sky was different from other scientists' earlier explanations primarily because he argued that Earth rotates on its axis. This idea distinguished his heliocentric model from the geocentric models prevalent at the time, which centered around the belief that Earth was at the center of the universe and did not move.