Don't tell me that man doesn't belong out there. Man belongs wherever he wants to go - and he'll do plenty well when he gets there.

I have learned to use the word "impossible" with the greatest caution

It will free man from the remaining chains, the chains of gravity which still tie him to this planet.

Man is the best computer we can put aboard a spacecraft... and the only one that can be mass-produced with unskilled labor.

Our sun is one of 100 billion stars in our galaxy. Our galaxy is one of billions of galaxies populating the universe. It would be the height of presumption to think that we are the only living things in that enormous immensity.

There is just one thing I can promise you about the outer-space program - your tax-dollar will go further.

We can lick gravity, but sometimes the paperwork is overwhelming.

Research is what I'm doing when I don't know what I'm doing.