Julian's Awesome Crossword Puzzle

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Across
  1. 1. heat
  2. 3. the outside of something
  3. 5. how cold or hot something is
  4. 6. the world
  5. 7. system the sun and planets that move around it
Down
  1. 2. how much of something there is
  2. 3. provided what is needed for something
  3. 4. the study of stars and planets