Across
- 2. making a complete spin on an axis
- 3. an imaginary line that Earth rotates around
- 6. the outermost covering or layer
- 7. a natural satellite that orbits a planet; some planets have no moons, and others have over 60 moons
- 9. the third planet from the Sun and the only planet in the solar system where life exists
- 10. making a complete turn around another object
Down
- 1. the layer of gas surrounding planet Earth that is held in place by gravity
- 4. bowl-shaped indents or cavities on the surface of a planet, moon, or asteroid that are caused by a collision with another object, such as a meteorite
- 5. the heaviness of an object; the force of gravity on mass is the weight
- 6. the star at the center of the solar system that supplies heat and light to Earth; its enormous gravity keeps the solar system in orbit
- 8. the path one object takes as it revolves around another object in space