Fear and worry are emotions that cloud the mind from being able to think clearly, to remember what the procedures are to deal with that emergency.

The life expectancy of people going to Mars may be decreased by the higher level of radiation that they receive.

I want people to go into space, to orbit around the world a few times, even to stay there for 24 hours and then come back to where they took off. And I also want people with a low income to be able to do that, not only rich people.

As a student, I wrote English reports on science fiction.

There's a tremendously satisfying freedom associated with weightlessness. It's challenging in the absence of traction or leverage, and it requires thoughtful readjustment. I found the experience of weightlessness to be one of the most fun and enjoyable, challenging and rewarding, experiences of spaceflight. Returning to Earth brings with it a great sense of heaviness, and a need for careful movement. In some ways it's not too different from returning from a rocking ocean ship.

I've been to the Titanic in a yellow submarine and the North Pole in a Russian nuclear ice breaker.

My own American Dream was to serve my country as best I could and make a difference in America - and in the world.