"Pale Blue Dot"

One of the world's most iconic photos of Earth, highlighted in the image by the blue circle, the "Pale Blue Dot" photograph was taken by the Voyager 1 spacecraft on July 6th, 1990 from roughly 4 billion miles away. The image was popularized in 1994 by astronomer Carl Sagan, who featured the image and his reflections on it in book "The Pale Blue Dot," and since then by the mass dissemination of the photo on the internet. While far from being the first immensely popular image of space or space travel, the "Pale Blue Dot" image has endured as a representation of the human fascination with the cosmos and our place within it.

Photo by NASA.

Source: http://upload.wikimedia.org/wikipedia/commons/7/71/PaleBlueDot.jpg