"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."