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

If we continue at this leisurly pace, we will have to pass Russian customs when we land on the moon.

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

I believe that the time has arrived for medical investigation of the problems of manned rocket flight, for it will not be the engineering problems but rather the limits of the human frame that will make the final decision as to whether manned space flight will eventually become a reality.

Science does not have a moral dimension. It is like a knife. If you give it to a surgeon or a murderer, each will use it differently.

Man is not made for space. But with the help of biologists and medical doctors, he can be prepared and accommodated.

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.