Across
- 1. round or flattened balls; contain only old stars
- 6. instrument that can spread the light into different wavelengths
- 7. range of wavelengths that stars emit
- 9. lifetime of a star depends on this
- 12. contracting gas and dust forms a large cloud called
- 14. force that tends to pull together the matter in stars
- 15. measure of the amount of light received on earth
- 16. huge group of single stars, star systems, star clusters
Down
- 2. Distance that light travels in one year
- 3. binary stars
- 4. Measure of the amount of light a star gives off
- 5. patterns of stars in the sky
- 8. active young galaxies with black holes at their centers
- 10. has bulge in middle and arms spiral outward
- 11. no regular shapes; generally bright, young stars
- 13. enormous explosion