It was obvious to me that we could never colonize Mars without reusability, any more than America would have been colonized if they had to burn the ships after every trip.

I'm personally a moderate and a registered independent, so I'm not strongly Democratic or strongly Republican.

I think it matters whether someone has a good heart.

You want to be extra rigorous about making the best possible thing you can. Find everything that's wrong with it and fix it.

We're running the most dangerous experiment in history right now, which is to see how much carbon dioxide the atmosphere can handle before there is an environmental catastrophe.

When something is important enough, you do it even if the odds are not in your favor.

I realized that a methane-oxygen rocket engine could achieve a specific impulse greater than 380.