The space shuttle is a better and safer rocket than it was before the Challenger accident.

But even in elementary school and junior high, I was very interested in space and in the space program.

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.

So most astronauts are astronauts for a couple of years before they are assigned to a flight.

You know, I go around the country a lot.

When you're getting ready to launch into space, you're sitting on a big explosion waiting to happen.

One thing I probably share with everyone else in the astronaut office is composure.