Space is not just going up and coming back down again. Space is getting into orbit and being there, living there, establishing a presence, a permanence.

I suggest that going to Mars means permanence on the planet - a mission by which we are building up a confidence level to become a two-planet species.

Presence is more than just being there.

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.

I think both the space shuttle program and the International Space Station program have not really lived up to their expectations.

My expertise is the space program and what it should be in the future based on my experience of looking at the transitions that we've made between pre-Sputnik days and getting to the moon.