Across
- 3. Who has found evidence that there may have been once water on mars
- 4. Has almost no atmosphere
- 6. What planet's diameter is 12,712 km
- 7. Ranges in thickness and composition, is made up of gases, and can change as a result of sunlight
- 8. Mercury, Venus, Earth, and Mars
- 9. ”To move repeatedly around”
Down
- 1. This planet's atmosphere is contained of mostly carbon dioxide.
- 2. A planet that is like the Earth in some ways
- 4. A celestial object that orbits a planet
- 5. What planet's diameter is 143,000 km