The Earth in the Universe

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Across
  1. 2. : a massive collection of stars, planets, gas, and dust
  2. 3. : the path planets follow around a star
  3. 5. : cloud of gas and dust
Down
  1. 1. : scientists use this to map the universe
  2. 2. : a satellite that maps stars
  3. 4. : a very famous telescope