Space crossword

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Across
  1. 4. relating to life on Earth, or the world
  2. 7. opposite of a black hole
  3. 8. sun's atmosphere
Down
  1. 1. means 'the universe in order and harmony'
  2. 2. large explosion that scientists believed created the universe
  3. 3. invisible form of matter that exists in space
  4. 5. no gravity
  5. 6. a group of stars