Nightfall is a short story set on a planet in which it is never fully dark. A group of scientists has discovered an irregularity in the orbit of the planet around its six suns; it is determined that soon, the planet will be plunged into the first true darkness it has known for centuries. As another scientist discovers evidence of past societal collapses, the consensus is that full darkness will drive people insane. This story contains themes of solitude, the vastness of the universe, and existentialism.
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