My vision is for a fully reusable rocket transport system between Earth and Mars that is able to re-fuel on Mars - this is very important - so you don't have to carry the return fuel when you go there.

Whenever I want to laugh, I read a wonderful book, 'Children's Letters to God.' You can open it anywhere. One I read recently said, 'Dear God, thank you for the baby brother, but what I prayed for was a puppy.'

Time travel was once considered scientific heresy, and I used to avoid talking about it for fear of being labelled a 'crank.'

Reputation is what men and women think of us; character is what God and angels know of us.

It is time to remember that old wisdom our soldiers will never forget: that whether we are black or brown or white, we all bleed the same red blood of patriots, we all enjoy the same glorious freedoms, and we all salute the same great American Flag.