Scientific inquiry shouldn't stop just because a reasonable explanation has apparently been found.

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 you love what you do, you'll be your best at it compared to anything else you might have chosen as a career. Or at least you will love it more, and you won't lead a depressed day of your life.

When NASA dreams big America dreams big. People...kids say, 'I want to do that when I grow up'. Because you want to do what's visible to you.

You don't need to be a scientist to know Earth's age or that life evolved. You just need be one who embraces objective truths

America has an economy reversing relative to other nations in the world. And I want to turn that around. And one way I know to turn it around is to get everyone excited about what it is to innovate again.

No one is dumb who is curious.