I was always very interested in science, and I knew that for me, science was a better long-term career than tennis.

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

But when I wasn't working, I was usually at a window looking down at Earth.

I didn't really decide that I wanted to be an astronaut for sure until the end of college.

The astronauts who came in with me in my astronaut class - my class had 29 men and 6 women - those men were all very used to working with women.

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

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.

We can see cities during the day and at night, and we can watch rivers dump sediment into the ocean, and see hurricanes form.

The view of Earth is spectacular.

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

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

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!

Even though NASA tries to simulate launch, and we practice in simulators, it's not the same - it's not even close to the same.

On both of my flights, everything went very well.

Because I was a tennis player, Billie Jean King was a hero of mine.

It takes a few years to prepare for a space mission.

I do a lot of running and hiking, and I also collect stamps - space stamps and Olympics stamps.

I don't have any nicknames.

Different astronauts sleep in different ways.

On a standard space shuttle crew, two of the astronauts have a test pilot background - the commander and the pilot.

NASA has to approve whatever we wear, so there are clothes to choose from, like space shorts - we wear those a lot - and NASA T-shirts.

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

I felt very honored, and I knew that people would be watching very closely, and I felt it was very, very important that I do a good job.

My background is in physics, so I was the mission specialist, who is sort of like the flight engineer on an airplane.

I liked math - that was my favorite subject - and I was very interested in astronomy and in physical science.

For quite some time, women at NASA only had scientific backgrounds.

The most anxious time was during launch, just because that is so dramatic.

I was always very interested in science, and I knew that for me, science was a better long-term career than tennis.

Some astronauts sleep in sort of beds - compartments that you can open up and crawl into and then close up, almost like a little bedroom.

No, I think most astronauts recognize that the space shuttle program is very high-risk, and are prepared for accidents.

Then during the mission itself, I used the space shuttle's robot arm to release a satellite into orbit.

The pressure suit helps if something goes wrong during launch or re-entry - astronauts have a way to parachute off the shuttle. The suits protect you from loss of pressure in case of emergency.

So most astronauts getting ready to lift off are excited and very anxious and worried about that explosion - because if something goes wrong in the first seconds of launch, there's not very much you can do.

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

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.

So I decided on science when I was in college.

I had both male and female heroes.

After the Challenger accident, NASA put in a lot of time to improve the safety of the space shuttle to fix the things that had gone wrong.

Yes, I did feel a special responsibility to be the first American woman in space.

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

The stars don't look bigger, but they do look brighter.

The food isn't too bad. It's very different from the food that the astronauts ate in the very early days of the space program.

All adventures, especially into new territory, are scary.

For a long time, society put obstacles in the way of women who wanted to enter the sciences.

For whatever reason, I didn't succumb to the stereotype that science wasn't for girls. I got encouragement from my parents. I never ran into a teacher or a counselor who told me that science was for boys. A lot of my friends did.

I did not come to NASA to make history.

I have a lot of common sense. I know what needs to be done and how to approach it. I have an ability to work with people on large enterprises.

I think it's important for little girls growing up, and young women, to have one in every walk of life. So from that point of view, I'm proud to be a role model!

I've spent my whole life not talking to people, and I don't see why I should start now.