Space Crossword :)

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Across
  1. 2. an object with a gravitational field so strong that nothing can escape its pull, not even light
  2. 5. substances or elements with unstable atomic nuclei that spontaneously releases energy
  3. 6. something existing or travelling in space between different galaxies
  4. 7. the moment the sun appears directly overhead of the equator
  5. 8. a building equipped with specialised instruments such as telescopes
Down
  1. 1. the continuous range of all possible frequencies
  2. 3. extremely large
  3. 4. any object that orbits or circles a object in space