Across
- 4. first stage of a stars formation
- 5. a large cloud of gas
- 6. accurate scale of entire solor system
- 8. universe exploded
- 9. space and everything in it
- 10. the blue white core that is left behid and cools
- 12. a group of single stars
Down
- 1. the brightness the star would have if it were at a standard distance from earth
- 2. brightness seen from earth
- 3. provides enough energy to create the heaviest elements
- 7. distance that travels in one year
- 11. large telescopes have spectrographs to --- light