science crossword

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Across
  1. 5. small dense star
  2. 7. sudden increase in brightness
  3. 8. how the universe began
  4. 9. the galaxy we are in
Down
  1. 1. where everything is
  2. 2. used to measure
  3. 3. the displasment of central lines
  4. 4. cloud of gas and dust
  5. 6. system of stars