Blast off!

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Across
  1. 2. We see tons and tons of these on clear nights, and they can form constellations
  2. 3. Blast off! when this takes off
  3. 5. You can use this to see stars and planets up close!
  4. 6. Someone who goes to outer space
  5. 8. An unknown creature from space
Down
  1. 1. In Zero _______, you can float around
  2. 2. #3 wears this to breathe or walk on the moon
  3. 4. There are many phases of this, including Full, New and Waning Crescent
  4. 7. The Earth (and everything else in our solar system) orbit around it