Memorial held for astronaut Neil Armstrong Mr Cernan was followed by a slow and solemn version of the song "Fly Me to the Moon" by singer Diana Krall. The service also included excerpts from a speech 50 years ago by John F Kennedy in which he said America chose to send men to the moon not because it was easy, but because it was hard. The scratchy recording of the young president said going to the moon was a goal that "will serve to organise and measure the best of our energies and skills, because that challenge is one that we're willing to accept, one we are unwilling to postpone." Shortly after that speech in 1961 at Rice University, Armstrong, not yet an astronaut but always a gifted engineer, was already working on how to land a spaceship on the moon, Nasa administrator Charles Bolden recalled. Snow talked of the 12-year-old Armstrong who built a wind tunnel. But most of Armstrong's friends and colleagues spent time remembering the humble Armstrong. Snow called him a "regular guy" and "the most reluctant of heroes." Nasa administrator Charles Bolden, a former astronaut, said Armstrong's humility and courage "lifted him above the stars." Bolden read a letter from President Barack Obama saying, "the imprint he left on the surface of the moon is matched only by the extraordinary mark he left on ordinary Americans." Armstrong commanded the historic landing of the Apollo 11 spacecraft on the moon July 20, 1969. His first words after stepping onto the moon are etched in history books: "That's one small step for man, one giant leap for mankind." Armstrong insisted later that he had said "a" before man, but said he, too, couldn't hear it in the recorded version. Armstrong and Aldrin spent nearly three hours walking on the lunar surface and left behind a plaque that read: "Here men from the planet Earth first set foot upon the moon. July 1969 A.D. We came in peace for all mankind. In all, 12 American astronauts walked on the moon before the last moon mission in 1972. Armstrong was a US Navy aviator. He joined NASA's predecessor agency in 1955 as a civilian test pilot and later, as an astronaut, flew first in Gemini 8 in 1966. After the moon landing he spent a year in Washington as a top official at the space agency, but then he left Nasa to teach aerospace engineering at the University of Cincinnati. He later was chairman of two electronics companies, but mostly kept out of the public eye. A private service was held earlier in suburban Cincinnati for Armstrong, who will be buried at sea.