I think sometime we will go to Mars and I think we'll explore it with humans sometime, but I think it's really wise to do all the robotic exploration ahead of time and learn as much as possible. Once we have learned as much as possible with the robots, then that's the time to send people, and let them then continue the research that the robots have started.

If there is one thing I’ve learned in my years on this planet, it’s that the happiest and most fulfilled people I’ve known are those who devoted themselves to something bigger and more profound than merely their own self interest.

To get your name well enough known that you can run for a public office, some people do it by being great lawyers or philanthropists or business people or work their way up the political ladder. I happened to become known from a different route.

I don't know what you could say about a day in which you have seen four beautiful sunsets.

I think that it's good for us to be able to travel in space and do research in space, and I emphasize the research, because space travel to me is far more than just seeing how far we can go.

By its very definition, civic responsibility means taking a healthy role in the life of one's community. That means that classroom lessons should be complemented by work outside the classroom. Service-learning does just that, tying community service to academic learning.

We thought that the odds of things working OK were up in the upper 90 percent or we wouldn't have gone. But the - there were some problems cropped up on the flight but was able to take care of those OK and - although they were things that we hadn't really trained that much for. But it was the time of the Cold War and so there were was a lot of pressure on the - to get going and the Russians were claiming that they were - Soviets were claiming they were ahead of us in technology.