The Pale Blue Dot is a photograph of planet Earth taken in 1990 by the
Voyager 1 space craft from a record distance of about 6 billion kilometers
from Earth. In the photograph, Earth is shown as a tiny dot (0.12 pixel in
size) against the vastness of space. The Voyager 1 spacecraft, which
had completed its primary mission and was leaving the solar system, was
commanded by NASA to turn its camera around and to take a photograph of
Earth across a great expanse of space, by the request of Carl Sagan.
 

"From this distant vantage point, the Earth might not seem of any
particular interest. But for us, it's different. Look again at that dot.
That's here, that's home, that's us. On it everyone you love, everyone you
know, everyone you ever heard of, every human being who ever was, lived
out their lives. The aggregate of our joy and suffering, thousands of
confident religions, ideologies, and economic doctrines, every hunter and
forager, every hero and coward, every creator and destroyer of
civilization, every king and peasant, every young couple in love, every
mother and father, hopeful child, inventor and explorer, every teacher of
morals, every corrupt politician, every "superstar," every "supreme
leader," every saint and sinner in the history of our species lived there
– on a mote of dust suspended in a sunbeam.

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 the great enveloping cosmic
dark. In our obscurity, in all this vastness, there is no hint that help
will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor 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. 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