“These days there seems to be nowhere left to explore, at least on the land area of the Earth. Victims of their very success, the explorers now pretty much stay home.”

“In more than one respect, the exploring of the Solar System and homesteading other worlds constitutes the beginning, much more than the end, of history.”

“Our particular causality scheme has brought us to a modest and rudimentary, although in many respects heroic, series of explorations. But it is far inferior to what might have been, and may one day be.”

“A new consciousness is developing which sees the earth as a single organism and recognizes that an organism at war with itself is doomed. We are one planet. One of the great revelations of the age of space exploration is the image of the earth finite and lonely, somehow vulnerable, bearing the entire human species through the oceans of space and time.”

“The Earth is the only world known so far to harbour life. There is nowhere else, at least in the near future, to which our species could migrate. Visit? Yes. Settle? Not yet. Like it or not, for the moment, the Earth is where we make our stand. It has been said that astronomy is a humbling and character-building experience. ... To me, it underscores our responsibility to deal more kindly with one another and to preserve, and cherish, the pale blue dot; the only home we've ever known.”

“It goes with a courageous intent to greet the universe as it really is, not to foist our emotional predispositions on it but to courageously accept what our explorations tell us.”

“We are made of stellar ash. Our origin and evolution have been tied to distant cosmic events. The exploration of the cosmos is a voyage of self-discovery.”