Usually the wacky people have the breakthroughs. The smart people dont.

I like to call the difference between research and development. Some people use that interchangeably. They'll say R&D. They're two totally different things.

With any luck, by the time NASA's space probe hits Pluto, you'll be booking a spaceflight with a privately run suborbital airline.

By 1931, after a few years' experience of flying scheduled airlines, those planes were operating at roughly 600 times the safety of the space shuttle. I look at safety not in terms of fatalities per passenger-mile, but when you get in and close the door, what is the risk of dying on this flight?

A NASA astronaut and a Russian cosmonaut can't be creative. He has to follow a predetermined detailed checklist written by an engineer and if he gets a little creative he'll never fly again.

The Russians did much bigger space launch vehicles for launching satellites and for getting men in orbit. They did that much sooner than America because America was very good at something else.

We didn't have practical model rockets in the '50s. The ones we made were very dangerous and the kids that played with them didn't have all their fingers, and sometimes were blind in one eye.