Oologies

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Across
  1. 2. The study of heat.
  2. 5. The study of sleep.
  3. 6. The study or exploration of caves.
  4. 7. The study of air and atmosphere.
Down
  1. 1. The study of kidneys.
  2. 3. The study of life in outer space.
  3. 4. The study of moon.