What does it feel like to blast off from Earth in a rocket, knowing that you will not see your family, feel the wind on your face, or taste fresh-cooked food for a whole year?

When National Geographic caught up with Kelly by phone in Las Vegas, he explained how a chance encounter with a book set him on his course to the stars, why he believes we are already capable of traveling to Mars, and how he coped in space after hearing the news that his twin brother’s wife, Gabby Giffords, had been shot. [See photos of Kelly’s triumphant return to Earth.]

I was on my second spacewalk. It was long and tiring and toward the end of it,