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When alan shepard returned from his first spaceflight, he developed a medical problem with his inner ear and was not able to go to space again until 1971, when he went to the moon with astronauts stuart roosa and edgar mitchell. alan shepard accomplished at least two unique firsts in space for the united states because he was the first american to go to space in 1961 and the first person to hit a golf ball on the moon to show its lower gravity in 1971. when he wasn't in space, alan shepard was chief of nasa’s astronaut office, from where he retired in 1974, worked in private business, and did volunteer work to support education and help people learn about spaceflight. alan shepard was an astronaut who became the first american in space on his first spaceflight, went to the moon and conducted experiments on his second spaceflight, and headed nasa’s astronaut office throughout his career.