Across
- 2. difference in position
- 3. very, very bright star
- 5. small, but very dense
- 7. system of many stars
- 9. neutral subatomic particle
- 10. brightness of a star
- 11. radiation from early universe
- 17. nothing can escape it
- 19. stars fusing hydrogen to helium
- 21. distance light travel
- 23. change in frequency of waves
Down
- 1. magnitude of celestial object
- 3. suddenly increases in brightness
- 4. likely a rapidly rotating neutron star
- 6. cloud, gas and dust
- 8. increase in brightness
- 12. universe originated from explosion
- 13. bigger than similar stars
- 14. reaction of atomic nuclei
- 15. proton without electric charge
- 16. small, very dense star
- 18. displacement of spectral lines
- 20. light, according to wavelength
- 22. scatter graph of stars