Across
- 1. A space where there are no particles
- 4. Orbits the earth
- 7. A large group of cells
- 8. Happens to wasted energy
- 9. Energy stored due to movement of an object
Down
- 2. Green substance in plants
- 3. Unit for measuring energy
- 5. Makes up most of the air
- 6. Planets spin on
- 7. Change in depth of water