US marks 50 years of manned space flight

To prepare for Shepard's flight, Nasa sent a chimp named Ham on a test flight in December 1960. He returned safely but chief rocket scientist Wernher von Braun was not happy with the rocket's performance and went back to the drawing board before attempting another test launch in March 1961, which cleared the way for Shepard's launch.

Already reeling from the shock of Russia's successful launch of a satellite into space, the US was further shaken by Yuri Gagarin's one-orbit flight on 12 April, 1961.

Alan Shepard was duly selected to be the first American in space via the Mercury programme. His spacecraft, Freedom 7, was only 3.5m tall and 1.9m wide.

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The Redstone rocket that propelled Shepard into space rises a few feet above the ground.

Frequent delays in getting the rocket ready that day forced Nasa to innovate on the spot. When Shepard had to urinate at one point — a completely unplanned event — he was told to simply go ahead and relieve himself.

The 25.2m-tall Redstone rocket was adapted from a missile that was 21m tall, while the fuel tanks were lengthened.

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Whereas Gagarin and the chimp Ham had little control of their capsules, Shepard was able to steer somewhat by hand during re-entry.

Once in orbit, Shepard did not have a window to see through and had to rely on a periscope. However, he was able to identify some features of the Florida coast.

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Shepard's flight took him 302 miles into the Atlantic, where he was rescued by helicopter.

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Shepard (right) was upset with Nasa, and von Braun in particular, for the delays of his launch that allowed Yuri Gagarin, instead of him, to become the first man into space. However, being second in the space race provided the incentive for President Kennedy, three weeks later, to give the challenge for the US to send a man to the moon and back by the end of the decade.

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Shepard went on to become the first man to hit a golf ball on the moon. After his Mercury flight he was grounded by Meniere's disease, but surgery allowed him to become commander of Apollo 14 and become the fifth man to step on the moon in 1971.

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Shepard died in 1998 and is commemorated by a statue in the US Astronauts' Hall of Fame at the Kennedy Space Center.

For more on this ZDNet UK-selected story, see Gallery: America's first small step into space — 50 years ago on ZDNet.com.

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