President John F Kennedy's speech at Rice University in 1961, which laid down the gauntlet for a landing on the Moon, seemed a daunting challenge at the time, especially when the US had only sent Alan Shepard on a 20-minute sub-orbital flight.

BBC: Neil Armstrong: 'Diffident' emissary of mankind

Okay, so technology was pretty much crap compared to what we take for granted today, especially when it came to the computational power required to get to the moon and back.

FORBES: Why I Named My Dog After Neil Armstrong

At the time Kennedy presented his vision few scientists thought a moon landing could be accomplished, especially in less than ten years.

FORBES: JFK's Twitter Friendly Vision