Across
- 1. system The Sun and objects that orbit it
- 4. The period of time that it takes a planet to complete one revolution around its star.
- 6. A force of attraction between all objects in the universe that is due to their masses.
- 9. A flattened circle
- 10. planet A planet having a rocky surface like Earth's. Also called "terrestrial planet."
- 11. A large body in space that orbits a star and does not produce light of its own
Down
- 2. A layer of gases that surrounds a planet, moon, or sun
- 3. The path that a body follows as it travels around another body in space
- 5. giant A large planet composed mainly of gas
- 7. planet Any of the four closest planets to the sun
- 8. an object that orbits a star, is round, not itself a star, and is large enough to have cleared the area of small objects