Question

1. what feature makes our solar system a heliocentric solar system?

○ all the planets have a retrograde rotation on their axis.
○ all the planets revolve around earth.
○ all the planets in revolve around their own moon.
○ all the planets revolve around the sun.

Explanation:

To determine the feature of a heliocentric solar system, we recall the definition: "heliocentric" means the sun is at the center. Let's analyze each option:

• Option 1: Retrograde rotation is not a defining feature of heliocentrism (most planets have prograde rotation, and rotation on axis is different from revolution around a central body).
• Option 2: A system where planets revolve around Earth is geocentric, not heliocentric.
• Option 3: Planets revolving around their own moon is incorrect (moons revolve around planets, not the other way around).
• Option 4: In a heliocentric system, all planets revolve around the sun, which matches the definition.

Answer:

D. All the planets revolve around the sun.