11. NASA made it clear that John Glenn would not be going back into space anytime soon – he was just too important as a national hero. Glenn left the astronaut corps in 1964 and decided to get into politics. At a 1969 news conference in Columbus, Ohio, he announced his candidacy for the Democratic nomination for U.S. senator. He lost out to fellow Democrat Howard Metzenbaum in the 1970 primary, but in 1974, Glenn prevailed and finally entered the Senate.

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Gene Herrick / AP