Question

Astronomy: Orbital Motion Unit Test
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Question
Which are features of Copernicus's model of the solar system? Select the three correct answers.(2 points)
Responses

The planets move in perfect circles.
The planets move in perfect circles.

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

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

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

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.

Copernicus proposed a heliocentric model where the Sun is at the center and the planets, including Earth, move around it in circular orbits. The stars were thought to be fixed to a celestial sphere surrounding the solar system.