The logistic requirements for a large, elaborate mission to Mars are no greater that those for a minor military operation extending over a limited theatre of war.

It takes sixty-five thousand errors before you are qualified to make a rocket.

The greatest gain from space travel consists in the extension of our knowledge. In a hundred years this newly won knowledge will pay huge and unexpected dividends.

All one can really leave one's children is what's inside their heads. Education, in other words, and not earthly possessions, is the ultimate legacy, the only thing that cannot be taken away.

If we were to start today on an organized and well-supported space program I believe a practical passenger rocket can be built and tested within ten years.

Development of the space station is as inevitable as the rising of the sun; man has already poked his nose into space and he is not likely to pull it back . . . . There can be no thought of finishing, for aiming at the stars-both literally and figuratively-is the work of generations, and no matter how much progress one makes, there is always the thrill of just beginning.

Basic research is what I am doing when I don't know what I am doing.