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Gus Grissom was the first astronaut to fly in space twice. Grissom was one of the seven original Mercury astronauts selected by NASA in 1959. He was the second American to fly in space, after Alan Shepard, and the first American to make a second spaceflight. Grissom's first spaceflight was in 1961 as the pilot of the Liberty Bell 7, which made a suborbital flight.