Science vocabulary.!!!!!!!!!!

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Across
  1. 3. a collection
  2. 5. year the distance that light Chan travel in 1 year(9.43 trillion kilometers)
  3. 7. the idea that the earth is the center of the heliocentric the idea that the sun is in the middle of the solar system
  4. 8. a large object that orbits a star
  5. 9. a small object that travels through space
Down
  1. 1. a collection of stars dust and gas’s that is held together by gravity
  2. 2. the idea that the universe began with a huge explosion
  3. 4. the study of the universe
  4. 6. all the matter in space