" Look again at that dot. That’s here. That’s home. That’s us… The Earth is the only world known so far to harbor life…Like it or not, for the moment the Earth is where we make our stand… There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. 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.

—CARL SAGAN, reflecting on a photograph of Earth taken by the Voyager 1 space probe from a distance of 6 billion kilometers (Pale Blue Dot, 1994) "

― Carl Sagan