Exploring Mars is a far different venture from Apollo expeditions to the moon; it necessitates leaving our home planet on lengthy missions with a constrained return capability.

We need to begin thinking about building permanence on the Red Planet, not just have voyagers do some experiments, plant a flag and claim success. Having them go there, repeat this, in my view, is dim-witted. Why not stay there?

I don't go through life verbalizing what I feel.

America's can-do spirit cast a warm glow across nations and cultures, generating more goodwill and support for our country's ideals and causes than had otherwise been possible.

The moon I see now is the same moon I saw before. Except that before, when I looked at it, it was in anticipation of what it would be like when I got there. That's behind me now.

Weve got to go [back to the moon]. But we dont want to stay too long. ... The ultimate goal is Mars.

Trips to Mars, the Moon, even orbit, will require that we provide astrotourists with as many comforts from home as possible, including paying each other.