* Astronomy

"The Naked Time" is an episode of the science fiction television series Star Trek. It was first broadcast September 29, 1966, and repeated on April 27, 1967. It is the fourth episode of the first season, written by John D. F. Black and directed by Marc Daniels. The story has a remake in Star Trek: The Next Generation, the episode "The Naked Now".
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Spoiler

"Where No Man Has Gone Before" is the second pilot episode of the science fiction television series Star Trek. It was produced in 1965 after the first pilot, "The Cage", had been rejected by NBC. Reportedly, Lucille Ball, who owned Desilu Studios (where the pilot was produced), persuaded NBC management to consider a second pilot, thereby exercising a special option agreement it had with Desilu, because she liked Roddenberry and believed in the project. The episode was eventually broadcast third in sequence on September 22, 1966, and re-aired on April 20, 1967. On July 12, 1969, it was the first episode to be shown in the UK by the BBC
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"Spock's Brain" is the first episode of the third season of the original science fiction television series Star Trek, first broadcast September 20, 1968
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Spoiler

"Charlie X" is a first season episode of the science fiction television series Star Trek first broadcast on September 15, 1966. It was repeated by NBC on June 1, 1967.
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