Across
- 2. having the conditions necessary to support life
- 5. a long, narrow groove that forms where water, lava, or other liquid flows
- 6. the mixture of gases surrounding a planet
- 7. a set of interacting parts forming a complex whole
- 9. all the liquid water and solid water (ice) on a planet
Down
- 1. the solid part of a rocky planet
- 3. all the living things on a planet
- 4. a feature that forms on the surface of a planet, such as a mountain, channel
- 8. information about the natural world that is used to support or go against (refute) a claim