The StarTalks - while kids can watch them, they're actually targeted at adults. Because adults outnumber kids five to one, and adults vote, and adults wield resources, and adults are heads of agencies. So if we're going to affect policy, or affect attitudes, for me, the adults have always been the target population.

There are two kinds of comments that I get. One is, oh, you're such a natural up there, and the other one is, you're working hard up there. And the ones who say I'm working hard are teachers, they're the educators; they're the people who are the performers. It's a huge investment of my psycho-emotional energy to pull that off and to make it look smooth.

And extracting one molecule's signature in spectral analysis from the rest of the signatures is hard work, sort of like picking out the sound of your toddler's voice in a roomful of screaming children during playtime. It's hard, but you can do it.

You can get an Egg McMuffin all day; you just can't get the hamburger all day.

If you get asteroids about a kilometer in size, those are large enough and carry enough energy into our system to disrupt transportation, communication, the food chains, and that can be a really bad day on Earth.

Many people feel small because they're small and the universe is big, but I feel big.

Lots of people think, well, we're humans; we're the most intelligent and accomplished species; we're in charge. Bacteria may have a different outlook: more bacteria live and work in one linear centimeter of your lower colon than all the humans who have ever lived. That's what's going on in your digestive tract right now. Are we in charge, or are we simply hosts for bacteria? It all depends on your outlook.