Across
- 5. distance between two points
- 9. Death of a large star
- 10. used in medical and astronomical fields
- 11. electromagnetic waves
- 13. All of space
- 15. the change in wave length
- 17. beginning point of something
- 18. Group of stars in space
Down
- 1. ___ waves provide us with light
- 2. A self-luminous celestial body
- 3. Made of hydrogen and helium
- 4. ____ consisting of waves moving at the speed of light
- 6. Rings of dust in the galaxy
- 7. standard unit to compare sizes of stars with our sun
- 8. ___ waves electromagnetic waves with long wavelengths
- 12. an instrument that collects light
- 14. Cloud of gas and dust
- 16. Speed of ___
- 18. ___ rays electromagnetic waves with very high energy