Lesson 3 & 4

1234567891011
Across
  1. 1. group of single stars, star systems,star clusters,dust, and gas bound together by gravity
  2. 8. a stars brightness as seen from earth
  3. 9. the first stage of a star's formation
  4. 10. The blue-white core that is left behind cools and becomes this
  5. 11. all of space and everything in it
Down
  1. 2. brightness of the star would have if it were a standard distance from earth
  2. 3. the distance that light travels in one year
  3. 4. his discoveries helped later scientists to ______ a more accurate scale of the entire solar system
  4. 5. when a star explodes
  5. 6. a large cloud of gas and dust containing an immense volume of material
  6. 7. large telescopes have spectographs to ______ light