This week marks the 50th anniversary of America's first manned mission to space. On 5 May 1961, a Mercury-Redstone rocket shot Alan Shepard to an altitude of 187km on a sub-orbital flight lasting under 16 minutes.
The US mission came just a few weeks after Yuri Gagarin had become the first human to fly in space – a propaganda coup for the Soviet Union.
Neal Thompson is the author of Light This Candle, a biography of the first American in space. He told BBC reporter Paul Rincon why he thinks Shepard, and his 1961 achievement, have been overlooked.
President Kennedy (L) with Shepard (R) on his return to Earth. Being second into space was a source of "lingering frustration" for Shepard
PR: Despite being America's first man in space, Alan Shepard's flight is perhaps less celebrated than other US space milestones such as John Glenn's first orbital flight. Why do you think that is?
NT: A couple of reasons: Yuri Gagarin flew first – I think that's the biggest one. I think Shepard was very frustrated by that too. Nasa had been hoping to launch his flight as early as late 1960.
THE FIRST AMERICAN IN SPACE
- Alan Bartlett Shepard Jr was born in 1923 in Derry, New Hampshire
- In 1950, he entered the Naval Test Pilot School in Maryland
- Was one of Nasa's original intake of astronauts – known as the Mercury 7
- Selected for the first American manned space mission – Freedom 7 – in 1961
- Freedom 7 flew about three weeks after the Soviet Union sent Yuri Gagarin into space
- Described by some colleagues as pushy or intimidating, but also enjoyed practical jokes
- The character of Alan Tracy in the 1960s TV series Thunderbirds is named after him
- Awarded the Congressional Medal of Honour and appointed as a UN delegate
- Commanded the Apollo 14 mission; the fifth man to walk on the Moon and the first to play golf on it
- Golf stunt used by politicians hostile to the space programme as an example of financial wastage
- Died in 1998 of leukaemia
- Too old to fly to the Moon?
But they kept postponing it – and for good reason. The Redstone rockets weren't the most reliable rockets – they had a bad habit of blowing up. So they kept delaying the scheduled flight over and over and Shepard felt that opened the window for the Russians to get there first.
Technologically, Shepard felt [the US was] ahead of the Russians and felt that we could have gone sooner. In addition to the Russians going first, they also orbited the Earth first. Shepard's flight was a great accomplishment, it was huge achievement for him to have been selected to go first [for the US], and then to have pulled off the flight almost flawlessly was very satisfying to him.
But the fact that it was a sub-orbital flight compared to Yuri Gagarin's orbital flight, combined then with John Glenn's flight the following year which had made multiple orbits of Earth – those are some of the reasons that Shepard got overlooked.
People probably remember him more for his golf shot on the Moon than being the first American in space. At the time, when the first seven US astronauts were competing for that flight, everyone wanted to be on the first one, thinking that would be the most historically relevant.
John Glenn was very frustrated that Shepard was chosen first. It's interesting that Glenn got the bigger prize by achieving the first orbital flight.
PR: Why do you think Shepard was selected for that flight? Do you think Nasa knew the first flight was likely to be overlooked, or did they feel Shepard's qualities best embodied the way they wanted to portray themselves as an agency?
NT: I think the latter is a real good description of what was at play with their