The prerequisite that people have a scientific or engineering degree or a medical degree limits the number of female astronauts. Right now, still, we have about 20 per cent of people who have that prerequisite who are female. So hey, girls: Embrace the very fun career of science and technology. Look at computer science. That's what I did.

Some people will always be volunteers to explore, and it is, in my mind, a privilege.

I am definitely a little more nervous for my colleagues when I'm working at mission control than I am myself, on the shuttle.

You're less apprehensive when you know what to expect. Also, the first flight is very important in this performance-driven culture I work in; it establishes your reputation. If you don't do well, it's probably your last flight.

I always call myself a space construction worker. We were only the second mission ever to go to the space station. There was nothing on board. We brought the first three tons of equipment, including some of the Imax camera stuff. We literally switched the light on to the station and walked in. It was an assembly mission.

I'm 45, and I'm still at school, essentially. Even after being assigned to the mission, I had to write a number of exams, with people commenting on my performance.

A lot of people, I think, would love to see the earth from above, wear a spacesuit. Certainly, when I was a kid, I wanted to wear a spacesuit.