In all the history of mankind, there will be only one generation that will be first to explore the Solar System, one generation for which, in childhood, the planets are distant and indistinct discs moving through the night sky, and for which, in old age, the planets are places, diverse new worlds in the course exploration.

The Cosmic Connection: An Extraterrestrial Perspective, Chapter 9 (p. 69), Dell Publishing, Inc. 1975