We can trace the elements. They were forged in the centers of high-mass stars that went unstable at the ends of their lives, they exploded, scattered their enriched contents across the galaxy, sprinkled into gas clouds that then collapsed and formed stars and planets and life.

If there were biologists among the extremophiles organisms that live in extreme conditions, they would surely classify themselves as normal and any life that thrived in room temperature as an extremophile.

Too many people view on [space exploration] as a luxury rather than as a fundamental driver to stimulate interest in science to everyone in the educational pipeline. It's vital to our prosperity and security.

Going into orbit around Earth - where the space station is today, and where the space shuttles and John Glenn and all those folks go-that's three-eighths of an inch above a schoolroom globe, just FYI. That's not very far from Earth. Yes, you are off Earth, but you're not really going anywhere yet. The moon was the only real destination.

If you're a scientist, and you have to have an answer, even in the absence of data, you're not going to be a good scientist.

People like death and mayhem.

When you advance a frontier and you do tomorrow what's never been done today, you have to innovate to make that happen. You become an innovation culture. When I grew up, every time I turned around it was, "Oh, here's the longest bridge or the deepest tunnel or the fastest airplane." And I originally thought that was just kind of like a pissing contest with men with too much testosterone. And then I realized that to make the tallest building you have to innovate. To make the fastest train you have to design the train in a way that it's never been designed before.