So when I think of, what is the meaning of life, to me, that's not an eternal unanswerable question. To me it is in arms reach of me every day.

We fail in even the simplest of all scientific observations-nobody looks up anymore.

If Neptune were analogized with a Chevy Impala in mass, then how big is pluto compared to that? Pluto would be a matchbox car sitting on the curb.

In astrophysics, we care about how matter, motion and energy manifest in objects and phenomenon in the universe. Stars are born. They live out their lives. They die. Some of the ones that die explode. Our sun will not be one of those, but it will die. And it'll take Earth with us. So we make sure we have other destinations in mind when that happens. And I've got it on my calendar.

Newton, Einstein, and every other great scientist in history...They all made mistakes. Of course they did. They're human! Science is a way to keep from fooling ourselves and each other.

I like seeing how people have succeeded when others would have presumed they would have failed, and others just go along with whatever everyone else does.

Asteroids have us in our sight. The dinosaurs didn't have a space program, so they're not here to talk about this problem. We are, and we have the power to do something about it. I don't want to be the embarrassment of the galaxy, to have had the power to deflect an asteroid, and then not, and end up going extinct.