There's a huge amount of pressure on every astronaut, because when you get right down to it, the experiments that are conducted on a space flight, or the satellites that are carried up, the work that's to be done, is important and expensive work, and you are up there for a week or two on a Space Shuttle flight. The country has invested a lot of money in you and your training, and the Space Shuttle and everything that's in it, and you have to do things correctly. You can't make a mistake during that week or two that you're in space.

You can picture pretty easily if there were a paying passenger aboard a rocket that failed, like Challenger failed. Certainly it would be a tragedy, and a tragedy for the company. They would have a hard time recovering from it.

So I saw many planets, and they looked just a little bit brighter than they do from Earth.

Different astronauts sleep in different ways.

Once you are assigned to a flight, the whole crew is assigned at the same time, and then that crew trains together for a whole year to prepare for that flight.

It takes a couple of years just to get the background and knowledge that you need before you can go into detailed training for your mission.

The most important steps that I followed were studying math and science in school. I was always interested in physics and astronomy and chemistry and I continued to study those subjects through high school and college on into graduate school. That's what prepared me for being an astronaut; it actually gave me the qualifications to be selected to be an astronaut.