We have no proof, But if we extrapolate, based on the best information we have available to us, we have to come to the conclusion that ... other life probably exists out there and perhaps in many places.

Well, I think we tried very hard not to be overconfident, because when you get overconfident, that's when something snaps up and bites you.

There are people I'll always love to listen to, and I'm always ending up discovering new songs by them, which is crazy. Like Stevie Wonder.

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.

Houston, that may have seemed like a very long final phase. The autotargeting was taking us right into a ... crater, with a large number of big boulders and rocks ... and it required ... flying manually over the rock field to find a reasonably good area.

NASA has been one of the most successful public investments in motivating students to do well and achieve all they can achieve. It's sad that we are turning the programme in a direction where it will reduce the amount of motivation and stimulation it provides to young people.

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