Across
- 2. A landform found on every inner planet
- 5. Venus is called Earth's sister______
- 8. The planet with carbon dioxide and acid rain clouds
- 9. Many of the planets contain this gas in the atmosphere
- 10. Many of the rocky planets are covered in ______________
- 11. The planet that has water in three different forms
- 12. Mercury is the planet closest to the __________
Down
- 1. Earth has the only suitable _____________ in the solar system to sustain life
- 3. The surface of Mars is primarily __________________
- 4. The planet that has no atmosphere
- 6. The planet that is half the diameter of Earth
- 7. Earth has at atmosphere primarily composed of _________________