The Pale Blue Dot is a photograph of Earth taken Feb. 14, 1990, by NASA's Voyager 1 spacecraft near the edge of our solar system looking back at the earth at a distance of 3.7 billion miles (6 billion kilometers) from the Sun.

Carl Sagan, Pale Blue Dot:

"Look again at that dot. That’s here. That’s home…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."

"Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in a great enveloping cosmic dark. [The same could be said for our solar system and our Milky Way Galaxy.] In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves." 

[The longer version is highly recommended!]