That is called the Pale Blue Dot. It was taken in 1990 by the Voyager 1 spacecraft. The "dot" is Earth, depicted against the vastness of space. It looks so lonely; it's hard to imagine how teeming with life the planet is. The best part of the picture, for me, is that it looks like Earth is caught in a shaft of light. Really it's not a beam of light shining on it directly but a refraction of sunlight in the Voyager's camera optics. But look at how tiny we are! Earth is taking up less than a pixel of this photograph.
Carl Sagan wrote a book called Pale Blue Dot: A Vision of the Human Future in Space. In it, he references the photograph, saying,
"The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds . . . It has been said that astronomy is a humbling and character-building experience. 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."
Sir, Say no More
Sir, say no more.
Within me ’t is as if
The green and climbing eyesight of a cat
Crawled near my mind’s poor birds.
-Trumbull Stickney
