Retain the vision for space exploration. If we turn our backs on the vision again, we're going to have to live in a secondary position in human space flight for the rest of the century.

A space program that truly goes somewhere! With his deeds, not only words, President Obama has revitalized our struggling space program.

Unfortunately, pioneers will always pave the way with sacrifices.

To me, money is a commodity that a person must have to function, not a goal in itself.

As we begin to have landings on the moon, we can alternate those with vertical launch of similar crew modules on similar launch vehicles for vertical-launch tourism in space, if you want to call it that adventure travel.

Russia perhaps is still entertaining the possibility that the moons of Mars might have access to ice or water.

I don't think we're going to build a 50-person spacecraft or a 100-person spacecraft.