I'm in favor of changing the destination of humans. There are a lot of manned missions that can be done, but not in the direction of the moon.

A space program that truly goes somewhere! With his deeds, not only words, President Obama has revitalized our struggling space program.

I don't believe any pair of people had been more removed physically from the rest of the world than we were.

I have no doubt that humans will go to Mars. And I feel that America has led so many things in space - we have invested so much, and we have a lot to gain - that America could and should be the nation that should lead the settlement of Mars.

The life expectancy of people going to Mars may be decreased by the higher level of radiation that they receive.

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.

Is the destiny of the human species to sit back and play with our mouse and computer and imagine, fantasize?