One of the things, and the most exciting, actually definitely the most exciting thing is, having children. You know, I didn't have children before. I had been married only a year before my space station mission, so having three-year-olds is a whole new experience and that's the new adventure. It may sound funny because people have kids every day, but having your own kids, having my own kids, was as fundamentally, or maybe even more fundamentally life changing then even flying in space.

Cooperating in something as visible as space exploration and space flight can only improve relations between the two countries because what happens is, you're working on a common project in a very visible light and so, you're motivated to not have conflicts with each other in other areas. And bringing up China is a good example. In the early '90's, China got serious about wanting to launch astronauts into space and they were actually quite successful in launching many communication satellites. They went ahead and in 2003 they launched their first astronaut into space.

If you think about the energy that a rocket engine has to put out and all the fuel and you're sitting on top of like a bomb. And on the Space Shuttle, that big orange tank is filled with liquid hydrogen and liquid oxygen, the white cell rocket boosters on the sides are filled with solid propellant. There's a lot of energy in all those chemicals there and you've got to control it in a way so it doesn't explode. So, there's a lot of plumbing, a lot of valving, a lot of control systems, and it's a very complicated thing. So, how do you bring the price of that down?

One of the biggest concerns about going out beyond lower Earth orbit is the radiation. We find that exercise seems to counteract a lot of the negative effects of space flight, like bone loss and muscle atrophy and cardiovascular systems issues. We exercise two hours a day on the station, which is a huge hit out of your day. It's great for staying in shape, but you know, it cuts into the productivity of the crew and if you look at how expensive it is to get a crew into space, if we can keep them healthy and have them exercise, but spend less time doing it, we can get more done.

The neatest thing about research and science is we don't necessarily know what's going to come down the pike. We think we know what we're working on. Oftentimes, discoveries are made when you're trying to discover something else. You end up accidentally discovering a different thing. So, one of those things might happen that enable us to have more efficient rockets.

This was the first time we had two ex-Soviet Cosmonauts in Houston. A lot of us, including me, viewed it with some skepticism, because I grew up during the Cold War, so I had been hit with all this propaganda all along that their stuff wasn't that good, it wasn't that safe and we were so much better. What I found out later was that their space stuff was very good and good enough that I was certainly comfortable flying on their equipment. So, it was kind of a revelation of sorts as the years went by and I think it underscores the importance right now of international cooperation.

If you increase the number of rockets you build and you buy, then it's the scale of the economy, the price is going to come down. It may not come down in order of magnitude, but if several commercial ventures start being successful and there becomes a bigger market for these rockets, the price will naturally come down a bit. That's why I think Excalibur Almaz, we're a little bit unique in that we don't look at our so-called competition with disdain, we want them to succeed and it needs to have more than one player. Even if we are successful, we couldn't handle the entire market ourselves.