Pat Norris was among the programmers who worked on the Apollo 11 mission that sent Neil Amstrong, Buzz Aldrin and Michael Collins to the Moon.
A specialist in radar technology, Norris moved from London to the US to work at TRW in Houston, Texas, providing ground based navigation for the mission.
He worked for Nasa on six missions from Apollo 8 to Apollo 13 and received an award from Neil Armstrong after the Apollo 11 mission, for his work on the navigation calculations.
In this video Norris speaks to Cliff Saran about the work he did for Nasa, the Apollo missions and his work on the Hubble space telescope.
Norris has written a book following on from his experience of the space programme, "Spies in the Sky", the story of how spy satellites prevented nuclear armageddon during the Cold War.
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