The jet stream is a very strong force and pushing a balloon into it is like pushing up against a brick wall, but once we got into it, we found that, remarkably, the balloon went whatever speed the wind went.

I think the thing about capitalism is it's an evil necessity, capitalism. Communism has been tried and failed, and socialism, that doesn't work very well. Capitalism works, but the problem about capitalism is it does mean that a few individuals become very wealthy. Therefore, I think those individuals have enormous responsibility to redistribute that wealth either by creating new businesses or creating new jobs and making sure that money just doesn't lie in a bank account for future generations.

I've used the Phoenix Centrifuge to replicate what the body's going to go through on the flight up. I've also done some gravity tests with ZERO-G [a charter-flight service in Arlington, Va., that uses modified Boeing 727s to simulate weightlessness], which went great.

It's better to say nothing than spend 1,000 words or an hour speech saying nothing. Get to the point.

To be a real entrepreneur you always have to be looking forward. The moment you rest on your laurels is the moment your competition overtakes you.

Build your own business team. Survival in business requires a synergy of skills.

The entrepreneurs who succeed usually want to make a difference to people’s lives, not just their own bank balances.