SPACE crossword!

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Across
  1. 2. natural satellite
  2. 4. big gas giants
  3. 6. big balls of burning gas
  4. 8. The only known planet to have life
  5. 9. closest star to Earth
Down
  1. 1. no rings
  2. 3. galaxy we live in
  3. 5. the number of planets in the solar system
  4. 6. what astrologists study
  5. 7. person who explores space