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Apollo astronauts signed and distributed space-themed envelopes to their families to serve as creative forms of life insurance; in the event that the astronauts didn’t return, their families were to sell the envelopes to provide for themselves. This one, which sold for $6710 at auction, was signed by the Apollo 11 crew and postmarked in Houston on 20 July 1969, the day Apollo 11 landed on the moon.