There are no practical alternatives to air transportation.

You must also realize that the stuff of excellence-truth, real scientific truth-can be elusive... It is too often covered by the heavy fog of fear and hidden by the darkness of your detractors.

So with imagination, ingenuity and audacity, explore, discover, change the world. And have fun while you're at it. Always take time out to love and to live. You're going to be busy, but never forget family and friends.

There are no practical alternatives to air transportation.

We want to build colonies on the Moon, Mars, the Moons of other planets, and even nearby asteroids. We want to make space tourism and commerce routine.

The real mark of your character comes from not how you react to your successes, of which I know there will be many. How you react to your failures, of which there will be, if you are bold, a number in your lifetime.