Carl Sagan once referred to the Earth as "where we make our stand."
And when seen by NASA's Mars rover Curiosity spacecraft across the vast expanse of space, that pale, blue dot he described suddenly makes sense. It's home -- but just one tiny speck barely visible in the infinite reach of space.
One very important speck, that is:
“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 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. 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. From Carl Sagan's "Pale Blue Dot: A Vision of the Human Future in Space."
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From the surface of the Red Planet, NASA's rover took a few minutes off from its science mission to gaze back at our planet, capturing a twinkling Earth spinning slowly in the sky.
The view of the twilight sky and Martian horizon shows Earth as the brightest point of light in the night sky -- the planet is a little left of center in the image, and just beneath it, almost invisible in the picture, our moon.
A human observer with normal vision, if standing on Mars, could easily see Earth and the moon as two distinct, bright evening stars, NASA said.
Not everyone was pleased with the view, however; a very sad Tweet from the parody Twitter account @SarcasticRover puts a different spin on the image:
I took a picture of the Earth last week and then I put "You are here" on it and laughed for an hour. Then I cried. http://t.co/QgkUqj4Lda— SarcasticRover (@SarcasticRover) February 6, 2014
In July 2013, NASA's Cassini craft took a similar image of Earth from over 900 million miles away, as the spacecraft spun around the planet. Researchers called it "the day the Earth smiled," because NASA asked Earthlings to smile and wave back at the spacecraft, knowing the exact moment the picture would be taken.
If you could somehow zoom in on that amazing picture, you'd see millions of smiling faces, as the planet paused to wave back to Saturn.
Researchers used the left eye camera of Curiosity's Mast Camera (Mastcam) to capture the new scene about 80 minutes after sunset on the 529th Martian day, or sol, of the rover's work on Mars -- Jan. 31, 2014.