Across
- 2. = A space with no air.
- 4. = What stars give off as heat and light.
- 5. = A gas that stars are mostly made of.
- 8. = The centre of a star.
- 9. = A gas made when hydrogen joins together in a star.
- 10. = A huge ball of hot gas that gives off light.
- 11. = Movement that makes sound.
- 13. = What sound travels through (like air).
- 14. = Particles that come from the Sun.
Down
- 1. = How hot something is.
- 3. = A force that pushes things together.
- 6. = When atoms join together to make energy in a star.
- 7. = Tiny pieces of matter.
- 12. = Tiny building blocks of matter.