I have dedicated my life to answering the great scientific questions of our time and to the incredible adventure of space exploration.
The Martian atmosphere is very thin. It's like our atmosphere at 100,000 feet.
When people left on the Oregon Trail from St. Louis, they knew that only a fraction of them would make it to the West Coast. But they went anyway.
The truth is, every single rocket launch off of planet Earth is risky.
One of the things that happens in space is that there is a fluid shift. You get a lot of extra pressure, and it fills your sinuses, and the horseradish is a miracle worker for cleaning that out.
The first thing to know about space food - it is the ambiance; it is the environment. It is not the food.
Small bodies in our solar system, like comets and asteroids, help us understand how the solar system formed and provide opportunities to advance exploration.
I think it's really a sign of great American strength that we do invest the money we do in technology, in these hard projects, in NASA.
Our country... invests a tiny fraction of 1 percent in NASA, and this is what's so amazing to me, is with that small investment, we do so much for the country.
A lot of people get home from work and sink into a good chair, the place in their life where they feel most comfortable. I get that comfort in space, the place where I most feel like I belong.
As soon as I could ride a bike... I was always riding over to the Museum of Science and Industry to explore. It's where I first began to develop a fascination with machines and scientific principles.
The things I like to do involve a lot of mental focus, a combination of physical and mental challenge. That is what mountain climbing is.
There are some things worthy of risking your life for.
The best would be to fly in space with family and friends.
After my spacewalks, I am quite exhilarated but also tired, similar to a workout on Planet Earth.
I was not really scared on my spacewalks. We practice so much and need to stay so focused that it has a calming effect on me. I do a kind of visualization and meditation in the airlock prior to going outside, to guide my first activities once I get out in space.
I can't imagine anywhere I'd rather be than outside the space shuttle in my space suit next to the Hubble Space Telescope.
We need to move off the planet. And Mars is the next best place.
I'm an incurable romantic. But I'm not an adrenaline junkie.
I don't particularly want to jump out of an airplane with a parachute if I don't have to. I don't want to go bungee jumping. I like adventure with a real purpose that I can buy into.
To help enable the kind of science Hubble is performing makes my life worthwhile.
Once we get beyond Mars, which formed from the same stuff as Earth, the likelihood that life is similar to what we find on this planet is very low.
I grew up on the south side of Chicago in the 1960s, and I think there was a synchronicity of events that inspired me to be an astronaut, and, of course, the backdrop is nothing less than Mercury, Gemini, and Apollo. That was a time in our nation where we aspired to great things, and we achieved them.
When I grew up on the south side of Chicago, it was kind of a rough neighborhood, and when my parents saw the prospect of my older sister going to middle school, high school, they decided that we would move to the north side of Chicago, Highland Park, and for me, that was a whole new ballgame.
Growing up in Highland Park, in high school, I had some very influential teachers: I had a math teacher who taught calculus that helped me learn to be in love with mathematics; I had a chemistry teacher who inspired us to work what was in the class and to go beyond.
Absolutely the most fun thing to do in space and rewarding thing, in many ways, is to look back at planet Earth.
I thrive with high-performance challenges in front of me.
I'm absolutely compelled for NASA to send international astronauts to Mars to find out if Mars ever harbored life.
All indications are that three and a half billion years ago, Mars looked like Earth. It had lakes. It had rivers. It had river deltas. It had snow-capped peaks and puffy clouds and blue sky. Three and a half billion years ago, it was a happening place. The same time on Earth, that's when life started. So did life start on Mars?
Getting a team of scientists on Mars could be transformative.
Here on Earth, we're exposed to asteroids hitting the Earth, eventual changes in the Sun, changes in the Earth's climate, things we're doing to the Earth's climate. If we want to survive, we need to become a multi-planet species. That's further down the road, but the first wave is going to be the explorers.
Life outside of Earth is probably going to be really hard to find.
Sciences are being unified by the search for life in the universe.