A hero to millions, Neil Armstrong has consistently shunned the limelight. To mark the 40th anniversary of the first manned Moon landing, author Andrew Smith travelled across America to discover why the man who first set foot upon the Moon remains such an enigma.
His words on being the first person ever to set foot on the Moon have been written into soundbite history - but in the four decades since Neil Armstrong became a household name, he has also increasingly become an enigma.
Unlike many of his contemporaries, Armstrong has refused to cash in on his fame and seemingly done everything in his power to diminish it.
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Being Neil Armstrong, presented by Andrew Smith (right), is on BBC Four at 0000 BST, Tuesday 7 July
So what has made Neil Armstrong such a reluctant hero, unsusceptible to the normal trappings of celebrity? And why won't he speak about his historic journey?
In his quest to uncover the man behind the spacesuit, Andrew Smith, author of Moondust: In Search of the Men Who Fell to Earth, decided to travel across America to meet people who have had an impact on Armstrong's life.
His conclusion is that Armstrong, now 78, believes simply that he did not deserve the attention.
"There were 400,000 people that worked on that [Moon landing] programme in various different ways and he thinks he didn't deserve all the credit just because he did the flying part," says Smith.
But Armstrong became a celebrity overnight. The Apollo 11 Moon landing marked a seismic shift in space exploration during a time when the world was captivated by space. It was watched by the largest television audience of its time, and President Nixon put in a congratulatory phone call just after the US flag was planted.
On the astronauts' return, Nasa sent them on a world tour.
Although Neil Armstrong initially went along with the celebrations, he always remained aloof; an elusive presence who preferred to talk about facts rather than feelings.
Neil Armstrong was the commander aboard Apollo 11
He started to decline speeches and interviews, eventually refusing to sign autographs and shying away from being photographed in public.
"To my knowledge he has done two television interviews in the last 40 years - and he says nothing about what he felt about anything. He will talk about matters of fact and that's it," says Smith. The author has been repeatedly refused an interview with Armstrong despite many requests, although the pair have had e-mail correspondence.
"And he didn't want to profit from it financially - even though a lot of the other Moon walkers have done - and amazingly he's stood by that. An auction house told me that if Armstrong spent just one afternoon signing autographs he could make a million dollars, but he's always refused."
Face of space
Two years after his historic journey, in August 1971, Armstrong left Nasa and decided to become a teacher.
"Ostensibly, it was a very strange decision. He could have done anything," says Smith.
Neil Armstrong, Michael Collins and Buzz Aldrin made up the crew
But if Armstrong thought a small aerospace engineering department at the University of Cincinnati would provide a refuge, he was to be disappointed.
"His old boss told me when he first arrived, he spent two hours every single day signing autographs for members of staff and students. Apparently there was a window right at the top of the wall and people used to go and make human pyramids just to look into his office.
"He dealt with it but he didn't like it, he couldn't walk across the campus without being constantly approached. He ended up going and spending a lot of his time flying, on his own, to get away from it."
Neil Armstrong's decision to keep a low profile contrasts with the man he shared the limelight with on that historic lunar landing.
Buzz Aldrin has become the face of space, courting media attention with a series of high-publicity manoeuvres including a Buzz Aldrin's Race into Space computer game and making a guest appearance in The Simpsons.
There are many more photos of Buzz Aldrin on the moon than Armstrong
For the 40th anniversary of the Moon landing, Aldrin has teamed up with hip-hop artist Snoop Dogg and producer Quincy Jones to create a rap single and video, Rocket Experience.
It's the kind of stunt that might send a shiver down Armstrong's spine.
But in an age of mass celebrity culture, how has Armstrong managed to remain so enigmatic?
"Everyone I met described Armstrong as a reserved and quiet man. I started to wonder whether they were protecting him, or maybe, in some ways at least, he was just a rather ordinary, nice man," says Smith.
And yet he concedes in many ways Armstrong is far from ordinary.
"He was an extraordinary pilot. He's flown the X-15, the fastest plane in the world, at 4,000mph (6,440km/h). He can fly anything; he is possibly the most distinguished pilot that has ever lived," says Smith.
"His generation were enchanted by flying, they were aviation pioneers. The Second World War pilots were their heroes. Armstrong never wanted to be a celebrity, he wanted to push the boundaries of flight."
That an ordinary small town boy from Ohio might struggle with becoming one of the most famous men on the planet is hardly surprising. But Smith thinks his steely, disciplined determination to shy away from the public eye is another of Armstrong's strengths.
Neil Armstrong only makes very rare public appearances
He says it helped him cheat death three times before he even got to the Moon.
"He always kept his cool. At one point on a flight he was just a fingernail away from not making it. Afterwards, fellow Nasa astronaut Alan Bean told me he saw Armstrong filling out an incident report but recalled him saying he'd just had a 'little difficulty'.
"He thought Armstrong had stubbed his toe or something, but actually he'd been two-fifths of a second away from death. He couldn't believe he was just calmly filling in forms as if nothing had happened - but that was the kind of man he was."
And then there is Armstrong's apparent eccentricity.
"The music he took on the mission to the Moon was deeply eccentric," says Smith. "Most astronauts took one classical piece, and one country and western.
"Armstrong took Dvorak's New World Symphony. But the other was theremin music - that eerie, wavy sound associated with sci-fi movies that goes 'woo woo'. On one hand it was the most perfect thing he could take, on the other it is massively eccentric - and that's kind of him."
And what about the poetic prose "That's one small step for [a] man, one giant leap for mankind" that slips off most people's tongues almost as easily as Shakespeare's famous lines "to be or not to be"?
Whether Armstrong was fed the line by a press officer or it was his own musing is the subject of much speculation, but one of his oldest friends has his own theory about its origin.
"'Kotcho' Solacoff says they used to play the game Mother May I? (also commonly known as Grandmother's Footsteps) - where you take small steps or giant steps - in the playground. He thinks it came from that. It struck me as really weird," says Smith.
Ordinary man or gentlemanly genius, maybe Armstrong's most celebrated act has been to remain - certainly in many ways - a man of sizeable mystery.
Below is a selection of your comments.
Armstrong is the ultimate professional. He was hired to do a job and he did it. Then he went home. William, Ilkley
A man who we all love for what he did. But a man who did what he did because he wanted to do it, not for the fame. Fame on that scale is a daunting life for some. Respect his wishes. No amount of money would make the fame easy. A man who is a living hero for doing something that was a thrill and a job for him. An adventurer who wants to enjoy the rest of his life in piece without constant attention from anyone he meets for him going to the moon was just another day. Living with fame is another thing all together David, Wrexham
While I can respect Armstrong's humbleness, a part of history will be lost if he never talks about his personal experiences. Joe, Idaho, USA
I recall reading at the time that Armstrong was chosen to be first on the moon as unlike all the other Apollo astronauts he was not a serving officer in the U.S. military. As a test pilot employed by the Locheed Aircraft Corporation he was technically a civilian. At the time it was important to be able to say the first man on the Moon was civilian and not military. John Mackie, Glasgow UK.
I would love to meet and talk with Neil Armstrong, however i hope that all will let him be as that is certainly his desire, he has earned it! Rich Allen, Houston Alaska
He not only redefined the frontiers of space expeditions but buried the crazy culture of celebrity. He indeed deserves our standing ovations. Besides he is not a funky footballer who is simply en cashing his few lucky kicks. He is an astronaut. Welcome to planet earth. Mohammad Athar, Dubai, UAE
Admirable not to let it go to his head but he could have used his celebrity to start humanitarian organizations. Fame doesn't have to be all bad. Too bad he didn't have the foresight to use his fame for the good of mankind in a bigger way than the moon landing hero. Phoenix, Honaunau, HI
Reserved or not, Neil Armstrong we are all proud of you. Ashwin, Bangalore
I've met him. He knows he's just a man and that's what I love about him. Luigi, tempe, az, USA
Neil will always be a hero to many. But I agree with him the entire team of the Apollo mission achieved something amazing, a true landmark in history. Like the writing of the bible or Koran it has influenced many. I believe that as a planet we should reach out and take historical steps, starting with reversing global warning. Andrew Hattam, Bury St Edmunds England
Good for Neil. He has guarded the legacy of Apollo and the memory of colleagues who died, with integrity and humility.Why should he be expected to dismantle all of that now? Simon Darnell, New York
Mr. Armstrong has made a difference to the world and to all of us. His famous words are being cited regularly in our household too. But we can only respect and admire him for his choice to remain his own man. Kari Wijbrans, Rheden, Netherlands
Humility as always displayed by Mr Armstrong during his career showed his greatness as a scientist. He is my man of the century! Dr Sunny Gbenebitse-Daniel, Lagos Nigeria
It is wonderful to have an unassuming hero. Thank you Ray Benson, Metlakatla, AK USA
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