There are always door openings. And gradually, it accumulates. The opportunities open up in front of you.

I'm sure that there are places in the deserts in Australia that could be similar to where we might want to go on Mars.

A hybrid human-robot mission to investigate an asteroid affords a realistic opportunity to demonstrate new technological capabilities for future deep-space travel and to test spacecraft for long-duration spaceflight.

The universe is the way it is. It's not going to be changed by supplications.

The beauty of Hawaii probably surpasses other places. I like the Big Island and the two mountains, Mauna Loa and Mauna Kea, where you can look out at the stars.

The pilgrims on the Mayflower landed at Plymouth Rock. To my knowledge, they didn't wait around for a return trip to Europe. You settle some place with a purpose. If you don't want to do that, stay home. You avoid an awful lot of risks by not venturing outward.

By refocusing our space program on Mars for America's future, we can restore the sense of wonder and adventure in space exploration that we knew in the summer of 1969. We won the moon race; now it's time for us to live and work on Mars, first on its moons and then on its surface.