"The Black Pits of Luna" is a science fiction short story by Robert A. Heinlein about a Boy Scout on a trip to the Moon and his novel way of finding his lost brother. Included as part of his Future History, it originally appeared in The Saturday Evening Post, January 10, 1948, and was collected in The Green Hills of Earth (and subsequently The Past Through Tomorrow).
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The Black Pits of Luna Wikipedia(Text) CC BY-SA