Across
- 6. galaxies that are grouped up
- 10. very large stars
- 13. stars pulled towards each other by gravity
- 14. large groups of stars
- 17. Hubble must be retreating from us at greater speeds
- 18. the hottest main sequence stars and the brightest
Down
- 1. relationships between the absolute magnitude and temperature of stars
- 2. that gives off pulsing radio waves
- 3. not even light can escape their surface
- 4. stars that end in brilliant explosions
- 5. a developing star not hot enough to engage in a nuclear fusion
- 7. remains of supernova events
- 8. universe began as a violent exploration
- 9. a unit to express distance
- 11. an area of stars
- 12. very bright stars
- 15. remains of low mass and medium mass stars
- 16. sudden brightness of stars