It's easy to sleep floating around - it's very comfortable. But you have to be careful that you don't float into somebody or something!

I don't have any nicknames.

I slept just floating in the middle of the flight deck, the upper deck of the space shuttle.

Anything from making a mistake on an experiment that would ruin some scientist on earth's experiment - career, potentially - to doing something wrong with the satellite that a country was depending on for its communications, to making some mistake that could actually cost you and the crew either a mission or your lives. So there is a lot of pressure that's put on every astronaut to just make sure that he or she understands exactly what to do, exactly when to do it, and is trained and prepared to carry it out.

My parents must have done a great job. Anytime I wanted to pursue something that they weren't familiar with, that was not part of their lifestyle, they let me go ahead and do it.

Studying whether there's life on Mars or studying how the universe began, there's something magical about pushing back the frontiers of knowledge. That's something that is almost part of being human, and I'm certain that will continue.

Well, we spend an awful lot of our time working and doing experiments. It's very busy up on the shuttle.