GENE Cernan, the last man to set foot on the moon, died earlier this week.
NASA administrator Charles Bolden, announced the death of the 82-year-old former Gemini and Apollo astronaut.
Mr Cernan, on leaving the moon in 1972, said: "As I take these last steps from the surface for some time into the future to come, I'd just like to record that America's challenge of today has forged man's destiny of tomorrow".
Mr Cernan started his career as a naval aviator before becoming the pilot for the Gemini 9 mission.
Mr Bolden said: "He became the second American to walk in space and helped demonstrate rendezvous techniques that would be important later.
"As a crew member of both the Apollo 10 and 17 missions, he was one of three men to have flown twice to the moon.
"He commanded Apollo 17 and set records that still stand for longest manned lunar landing flight, longest lunar surface extravehicular activities, largest lunar sample return, and longest time in lunar orbit.
"Gene's footprints remain on the moon, and his achievements are imprinted in our hearts and memories.
"His drive to explore and do great things for his country is summed up in his own words, 'We truly are in an age of challenge. With that challenge comes opportunity.
"The sky is no longer the limit. The word impossible no longer belongs in our vocabulary. We have proved that we can do whatever we have the resolve to do. The limit to our reach is our own complacency'."
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