Tax dollars intended for science education must not be used to teach creationism as any sort of real explanation of nature, because any observation or process of inference about our origin and the nature of the universe disproves creationism in every respect.

I tell personal stories associated with aspects of the theory, and I hope they are interesting and compelling. I don't feel you're going to change a grownup's mind in one reading. People have to be exposed to scientific ideas over and over again for years. It's also not a textbook.

If you meet somebody who says he or she has never dreamed of flying, I don't believe you. I mean, they're lying.

NASA is an engine of innovation and inspiration as well as the world's premier space exploration agency, and we are well served by politicians working to keep it that way, instead of turning it into a mere jobs program, or worse, cutting its budget.

The oncoming trouble I speak of is climate change. It's going to affect all of you in the same way the Second World War consumed people of my parent's generation.

Recommending or insisting on abstinence has been completely ineffective.

There's nothing I believe in more strongly than getting young people interested in science and engineering, for a better tomorrow, for all humankind.