Within 25 years, virtual reality meetings will be essentially transparent to being there in person. Once we can do this, the idea of climbing into an aircraft, and burning up huge quantities of fossil fuels to propel our bodies and briefcases full of papers, will seem absolutely backward.

At various times over 20 years, I did preliminary designs for aircraft like the Stratolaunch. For that whole time I was encouraging us to do something that almost everyone else felt you could not do.

The criticism is, once I get something flying, I lose interest in it.

To allow public access to orbit, we would need breakthroughs that would lower the cost by a lot more than an order of magnitude and increase safety by a factor of 100 as compared to every launch system used since the first manned space flight. I think airborne launch will be a significant part of the safety solution.

Virgin Galactic, which will be operating SpaceShipTwo, will be only one of several spacelines. The competitors for Virgin include the Russians, Bezos's Blue Origin, and possibly Rocketplane Kistler. And likely a couple of others who are smart enough not to tell people what they are doing!

Everything looks nonsensical before it works.

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.