Space Crossword puzzle

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Across
  1. 4. furthest planet from the sun
  2. 8. our sun and the objects that orbit around it
  3. 10. the star closest to earth
  4. 12. to turn on an axis
  5. 13. Saturn, Jupiter, Uranus and Neptune have it
  6. 14. planet that rotates on its side
  7. 17. planet closest to the sun
  8. 18. third planet from the sun
Down
  1. 1. dwarf planet with two moons
  2. 2. instrument used for seeing stars and planets
  3. 3. warmest planet; cloudy planet
  4. 5. a space traveler
  5. 6. It takes Earth 365 days to __ the sun
  6. 7. planet with the brightest rings
  7. 9. the red planet; humans have sent robots here
  8. 11. force that causes things to fall toward earth
  9. 15. number of stars in our solar system
  10. 16. large planet known for the Great Red Spot
  11. 17. Neil Armstrong was the first to walk on it