Across
- 2. Something that comes from living things.
- 5. A deep valley with steep sides, often carved by a river.
- 6. Anything that has mass and takes up space.
- 8. A vehicle used to explore the surface of planets.
- 10. A tool used to look at stars and planets from far away.
- 12. People who study stars and planets.
- 13. A tool used to remove unwanted things from liquids or air.
- 14. A strong metal used to make tools and buildings.
Down
- 1. Relating to the North or South Pole.
- 3. A path or passage, often for water to flow through.
- 4. Something that is hard to understand or explain.
- 5. A man-made waterway used for transportation or irrigation.
- 7. A type of gas that is often found in swamps or used as fuel.
- 9. The air around Earth or another planet.
- 11. A mountain that can erupt with hot lava, ash, and gases.