Universe, Stars, and Galaxies

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Across
  1. 2. method of measurement for stars
  2. 6. a lot of stars held together by gravity
  3. 8. two stars orbiting each other
  4. 11. group of hundreds or thousands of stars
  5. 12. study of the universe
  6. 13. our galaxy
Down
  1. 1. dense, light cannot escape
  2. 3. group of stars
  3. 4. stars core changes to a white glowing sphere
  4. 5. ball of glowing gas
  5. 7. all of the star systems, galaxies, dust
  6. 9. stars that are grouped closely together
  7. 10. biggest group of stars
  8. 11. explosion that occurs with a star's core