I would say keep supporting space flight, keep telling the public and the politicians why it's important to advance science and explore the galaxy. I encourage the Japanese to keep doing what they're doing.

Where we're operating is orbital adventures. We would offer five to seven days in low Earth orbit aboard our own spacecraft where customers would have the view of the Earth; get to experience really living in space, probably conducting some scientific investigations that we would piggyback onto those flights. So, they would have the whole experience, kind of a mini-experience of what professional astronauts have.

As commander I was responsible for the overall success of the mission, and so I had to know at least a little bit about everything.

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?

We were doing something called telemedicine, where we were using the ultrasound. One interesting application of this ultrasound is the possibility that you could possibly use it to measure critical bone areas during a long space mission and track if you're losing bone in these areas. On Earth, when they check you for bone loss, you get in this big machine. It's the size of a room and it's got a platform with an x-ray that scans your whole body and in critical areas and it takes a while and it just wouldn't be practical to have a machine like that in space.

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.

I had done everything I could do as an astronaut, and we have a long line of inexperienced astronauts waiting for their first missions, and so my role really should be to step aside and help them prepare for their missions, rather than to try to get another mission.