Coming down under a parachute is quite different as well. You hit the ground pretty hard, but all the systems work very well to keep it from hurting, so it doesn't even hurt when you hit. It was a great experience to be able to do both.

You saw Britain back in the early days of sailing ships. They were the sea power, the controlled the seas and they had colonies all over the world and then you can look at history and watch the way that their empire kind of crumbled. I certainly don't want that to happen to the United States in space technology.

It was in the back of my mind, even while I was going to school, but it wasn't until I was at university studying engineering that I thought, well what do I really want to do? And I kind of came back to that and I said, well the degrees I'm trying to get are going to qualify me to apply. And so, that's what I did after I finished my, or after I was getting my doctorates. That's when I first applied to NASA.

The Russians have been flying long duration crews since the early '70's. And in the early days, they've ended at least two missions early because of conflicts within the crew. So, they learned early on the importance of studying this and making sure you put the right crew together. Since we began our work together on the International Space station with the Russians in the early 2000's, NASA has started to learn the importance of this kind of work. And so, I think it's important work and we are not fully onboard and recognize it as important.

The United States, Russia, and China are the only three countries in the world that can launch astronauts into space. Mostly in the U.S. you see some companies trying to launch private commercial people into space, but nobody's done it yet. The only private vehicle that's made it into space so far is Spaceship 1 in 2004, and that was an effort that was funded by one of the Microsoft founders, and he spent about $20 million to develop this spacecraft to do a sub-orbital flight. And it's not the same as going into orbit, but it was a huge first step.

The ultrasound that has application not only in space for a long mission or for a mission to the Moon or Mars, but also in remote areas on the Earth. Not even just - I'm not even talking about expeditions like to the Antarctic, but just a remote area, a small town somewhere. The local doctor is not going to know everything, and so if that person can link in with a diagnostic ultrasound to the hospital in New York City through the internet, then they can do a very quick diagnosis of something that's wrong with someone that's in this remote area.

Of course, you'll have to meet the physical and psychological demands. A space walk takes a lot of energy.