Space technology has not changed the fundamental character of scientific development, but it has created many demands on science and has hastened many investigations that otherwise might not receive prompt attention A great deal is being said these days about the “impact” of space exploration on science. “Impact” is a harsh word, which perhaps explains the extent to which it has become fashionable in these harsh times. I have not consulted my dictionary because, having driven an automobile in heavy traffic for many years, I have direct physical experience with the word. I know what it means. In fact, all of us who have followed the accounts of the embryonic stages of lunar exploration in the form of the Ranger series obviously know what the commentator meant when he triumphantly shouted “Impact!” after an exciting sequence of pictures closer and closer to the surface of the moon.