astronomy puzzle

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Across
  1. 1. the sister planet of earth
  2. 6. the angle of which planets rotate
  3. 9. A sandy red planet
  4. 10. what gives Earth its ability to have breathable air
  5. 13. the exact opposite of a black hole
  6. 14. the galaxy we live in
  7. 15. was a planet and now is reclassified as a dwarf planet
  8. 17. dwarf planet in our solar system
  9. 18. the most well known space telescope launched in 1990
  10. 20. measurement of distance in space
Down
  1. 2. when the moon covers the sun during the day
  2. 3. the largest planet in our solar system
  3. 4. A hole in the fabric of space that sucks everything in
  4. 5. the smallest planet in our solar system
  5. 7. a series of rocks floating in space
  6. 8. the Hubbles predecessor
  7. 11. full of craters and doesn't rotate
  8. 12. what the planets revolve around
  9. 16. what pulls objects to the ground
  10. 19. the only planet with known life