Which are features of Copernicus's model of the solar system? Select the three correct answers.(2 points)

Question

Responses

All planets orbit the Sun at the same speed.
All planets orbit the Sun at the same speed.

The outer planets move in epicycles.
The outer planets move in epicycles.

Earth is fixed to a crystalline sphere.
Earth is fixed to a crystalline sphere.

The stars are fixed to an outer sphere.
The stars are fixed to an outer sphere.

The Sun is at the center.
The Sun is at the center.

The planets move in perfect circles.

Answer 1

The three correct features of Copernicus's model of the solar system are:

1. The Sun is at the center.
2. The planets move in perfect circles.
3. The stars are fixed to an outer sphere.

These features reflect the heliocentric nature of Copernicus's model, where the Sun is the central body and the planets, including Earth, orbit around it. Although Copernicus tried to maintain the idea of circular orbits, he later acknowledged that the orbits might not be perfect circles. However, under his model, the planets did not move in epicycles, which was more characteristic of the Ptolemaic (geocentric) model.