On both of my flights, everything went very well.

It was hard to become an astronaut. Not anywhere near as much physical training as people imagine, but a lot of mental training, a lot of learning. You have to learn everything there is to know about the Space Shuttle and everything you are going to be doing, and everything you need to know if something goes wrong, and then once you have learned it all, you have to practice, practice, practice, practice, practice, practice, practice until everything is second nature, so it's a very, very difficult training, and it takes years.

Science is fun. Science is curiosity. We all have natural curiosity. Science is a process of investigating. It's posing questions and coming up with a method. It's delving in.

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

All adventures, especially into new territory, are scary.

I've discovered that half the people would love to go into space and there's no need to explain it to them. The other half can't understand and I couldn't explain it to them. If someone doesn't know why, I can't explain it.

That's something that is almost part of being human and I'm certain that will continue.