The single thing which makes any man happiest is the realization that he has worked up to the limits of his ability, his capacity. It's all the better, of course, if this work has made a contribution to knowledge, or toward moving the human race a little farther forward.

Hey, we missed the whole thing.

The exciting part for me, as a pilot, was the landing on the moon. That was the time that we had achieved the national goal of putting Americans on the moon. The landing approach was, by far, the most difficult and challenging part of the flight. Walking on the lunar surface was very interesting, but it was something we looked on as reasonably safe and predictable. So the feeling of elation accompanied the landing rather than the walking.

I believe that every human has a finite number of heartbeats. I don't intend to waste any of mine running around doing exercises.

In much of society, research means to investigate something you do not know or understand.

No matter when you had been to this spot before, a thousand years ago or a hundred thousand years ago, or if you came back to it a million years from now, you would see some different things each time, but the scene would be generally the same.

As a boy, because I was born and raised in Ohio, about 60 miles north of Dayton, the legends of the Wrights have been in my memories as long as I can remember.