Across
- 4. An apparent force.
- 8. The place surrounding a planet.
- 9. A small rock orbiting the sun.
- 10. A person who goes to space.
- 11. An opening in the moon.
- 12. The circular motion planets make.
Down
- 1. A property of matter that stays the same.
- 2. A force that attracts things to the center of the earth.
- 3. The form of a fingernail or a sort of moon.
- 5. All existing matter and space.
- 6. A pattern of stars in the sky.
- 7. Garbage floating in space.
