#crater  a bowl-shaped depression formed by the impact of a meteorite or bomb
  supertype:  #natural_depression__naturaldepression__depression  a sunken or depressed geological formation
  subtype:  #collector  a crater that has collected cosmic material hitting the earth
  subtype:  #lunar_crater__lunarcrater  a crater on the Earth's moon
     subtype:  #Aristarchus  a bright crater on the moon
     subtype:  #Copernicus  a conspicuous crater on the moon

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