That's a picture of the Earth and Moon as seen from the planet Mars. Frankly, I didn't know we had anything in the Martian neighborhood with optics good enough to take a shot like that, and at first suspected it was a fake. But it's real, shot by the High-Resolution Imaging Science Experiment (HiRISE) on the Mars Reconnaissance Orbiter currently orbiting the red planet. Usually it's pointed down toward the ground. By the way, NASA says that's the west coast of South America in that picture, and in a higher-res version I can just make it out.
What strikes me is that we go to all the trouble of sending these spacecraft out to explore the unknown millions of miles away, yet are moved most powerfully when they point their cameras back at us. It's the same reaction the world had when the Apollo 8 astronauts became the first humans to see the far side of the Moon first-hand* and photographed Earth rising over the lunar horizon as they flew back around. To paraphrase Carl Sagan, everything you know and love, everything that ever happened in all of human history, all the life we have knowledge of anywhere in the universe, is on that fragile little blue sphere.
I've seen a few photos like this before. As I recall, one of the Voyager probes photographed the Earth-Moon pair as it soared away from us on its way out of the solar system. We send surrogate eyes out only to look back and see ourselves more clearly. These pictures get me every time.
* The Soviets took the very first pictures of the far side of the Moon via unmanned probe, which is why most of the craters back there have Russian names.