NASA selects seven men to become the first astronauts. They're all test pilots, prepared to risk their lives. No one has ever survived a vertical launch on top of a rocket, but it's the only way they know to put an astronaut into earth orbit. NASA and America's first astronauts, the Mercury Seven, are on a journey into the unknown. Six of the men ride into space, each launch taking NASA further forward in their quest to conquer space.
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