If you're trying to get someone who's sick with a fever off of a submarine and it's cold and raining outside, the only way in and out of a submarine, generally, is through a fairly narrow hatch.

The Navy's paid for you to go through school, and then they need doctors to go out and take care of people who are in various different parts of the world. I decided to pay back my time first as an undersea medical officer. I was stationed in Scotland.

Gravity pulls our bodily fluids down, like water in a glass goes to the bottom part of a glass. In space, the water doesn't stay in the bottom of the glass. It distributes itself evenly over time throughout the entire volume of the glass.

Other than motherhood, the eight years that I spent at the University of Wisconsin, Madison, I have incredibly fond memories of. It's a beautiful place, with four seasons up in Wisconsin. And really wonderful people.

I feel blessed to be here representing our country and carrying out th research of scientists around the world... I hope you could feel the positive energy that beamed to the whole planet as we glided over.

The microgravity or the very, very low amount of gravity that we have up in space forces some changes in different processes. It forces changes in us as human beings.

I can't think of anything specific growing up that pointed me toward NASA at all. I was interested in the Moon landings just about the same as everyone else of my generation. But I never really thought about being an astronaut or working in space myself.