History gets reinterpreted as time goes on. Many times, the participants are lost in the retelling of the story.

Mars, we know, was once wet and warm. Was it home to life? And what can living and learning to work on its rust-colored surface teach us about the future of our own planet, Earth? Answering those mysteries may hold the key to our future.

I shot down two airplanes in Korea, so I wasn't a slouch.

I think I need to continue to think and plan and marry all of the different things that we could do that make transportation in space from the earth to the space station, from the earth to the moon to space stations around the moon to visiting an asteroid.

Walking around on the moon was significantly easier than we'd thought it would be. There weren't any balance problems, so you weren't tumbling over.

There's a tremendously satisfying freedom associated with weightlessness. It's challenging in the absence of traction or leverage, and it requires thoughtful readjustment. I found the experience of weightlessness to be one of the most fun and enjoyable, challenging and rewarding, experiences of spaceflight. Returning to Earth brings with it a great sense of heaviness, and a need for careful movement. In some ways it's not too different from returning from a rocking ocean ship.

I'm not in favor of just taking short-term isolated situations and depleting our resources to keep our climate just the way it is today.