"Conquering the universe one has to solve two problems: gravity and red tape. We could have mastered gravity."

"A good scientist is a man with an original mind who can think straight, but who also has a practical sense of what is possible."

"I’m convinced that before the year 2000 is over, the first child will have been born on the Moon."

"I never worked for Hitler. I worked for the rockets."

"In this age of space flight, when we use the modern tools of science to advance into new regions of human activity, the Bible... remains in every way an up-to-date book."