Crash programs fail because they are based on theory that, with nine women pregnant, you can get a baby in a month.

I find it as difficult to understand a scientist who does not acknowledge the presence of a superior rationality behind the existence of the universe as it is to comprehend a theologian who would deny the advances of science.

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

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.

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.