This has been far more than three men on a mission to the Moon; more still than the efforts of a government and industry team; more, even, than the efforts of one nation. We feel this stands as a symbol of the insatiable curiosity of all mankind to explore the unknown.

Mars has been flown by, orbited, smacked into, radar examined, and rocketed onto, as well as bounced upon, rolled over, shoveled, drilled into, baked and even blasted. Still to come: Mars being stepped on.

People communicate in Twittering ways. I've learned how to do that.

Any observations from the Moon or a sense of realising this or that about the greater meaning of things wasn't as influential for me as the experience of coming back and dealing with being a person who's been to the Moon.

Astronauts working for the government will always need to be either pilots or mission specialists. Those who want to be pilots should have military experience - ideally, a test pilot background.

It was designed to have an impact on the stalemate over Mutually Assured Destruction with the Soviet Union. Us reaching the moon convinced Gorbachev and other leaders that the Soviet Union couldn't compete with the U.S., so they revised their agenda. But people have short memories.

I expected the unexpected and went [on the Moon] with an open mind. I think the visual scene was described by my words on first landing - "magnificent desolation." Magnificent for the achievement of being there, and desolate for the eons of lifelessness.