Unless we are able to commit to a permanent growing settlement [on Mars], then I don't think just going there with humans and coming back is worth doing. The expense of planning to come back is like the people who left Europe to come to America and then to turn around and go back to Europe, it really doesn't make any sense at all.

Going to Mars would evolve humankind into a two-planet species.

Training was very extensive, and we dealt with many recoveries from emergencies, and fortunately, participating and observing and existing through the reality of space was a once-in-a-lifetime experience and it was not marred by unexpected hazards or catastrophes.

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.

Kids, help your parents if they don't know how to use a smartphone.

As we reflect back upon the tragic loss of Challenger and her brave crew of heroes who were aboard that fateful day, I am reminded that they truly represented the best of us, as they climbed aloft on a plume of propellant gasses, reaching for the stars, to inspire us who were Earthbound.

I think humans will reach Mars, and I would like to see it happen in my lifetime.