If you're an adult and you choose not to believe in science, fine, but please don't prevent your children from learning about it and letting them draw their own conclusions.

I like to regard myself as someone who's capable of critical thought, that is to say, who can evaluate claims.

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.

Everyone, red state, blue state, everyone supports space exploration.

If you can command a lot of attention, that's what is valuable, and many in the commercial ecology would like to have a piece of that attention.

We must start to treat climate change as what it is - a threat to United States security. And we must not delay.

Scientists worldwide agree that the reduction needed to stabilize the climate is actually more like 80 percent.

Well, I think I was always sort of reflecting where I was and my sense of surroundings and ecology, urban or country, or foreign, living in Europe, very affected by all of that.