Across
- 1. planet made of gas
- 7. not being harmful to the planet
- 8. planet with ice
- 9. solar system is in it
Down
- 2. there are eight planets in it
- 3. mass of air that surrounds planets
- 4. the outside part or uppermost layer of something
- 5. the force of an object to pull another to it
- 6. separates inner planets from outer planets