#sky  outer space as viewed from the earth
  supertype:  pm#space (pm)  point or extent in space
  subtype:  #blue_sky  #mackerel_sky
  part of:  #Earth.terrestrial_planet
  part:  #cloud.atmospheric_phenomenon  a visible mass of water or ice particles suspended at a considerable altitude
  part:  #rainbow  an arc of colored light in the sky caused by refraction of the sun's rays by rain

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