Great photography often comes down to snapping the right subject from the right vantage point at the right time. This image from NASA is just that. It was taken by the camera onboard the Deep Space Climate Observatory (DSCOVR) satellite, one million miles away from Earth — the perfect spot to capture the Moon passing across the sunlit face of our planet.
That’s the curve of California and Mexico sliding away to the upper right of the planet while Australia creeps into view from the bottom left. Since the Moon is tidally locked, meaning only one side ever faces the Earth, this image shows its rarely-glimpsed far side.
DSCOVR’s Earth Polychromatic Imaging Camera actually takes 10 separate monochrome images — from ultraviolet to near infrared — in rapid succession, explains Rob Gutro in NASA's press release. The colors in this GIF come from combining red, green and blue channels. However, since the images are snapped one after the other, about 30 seconds elapse between the first visible color image and the last. The Moon moves in relation to the Earth during that time, so the three pictures aren't perfectly aligned. This discrepancy gives rise to a slight green cast on the leading edge of the Moon.
One of the DSCOVR scientists, Adam Szabo, noted that the moon looks relatively dim against the Earth. "Our planet is a truly brilliant object in dark space compared to the lunar surface," he says. The shine of a full moon hanging in the night sky is, after all, a reflection of that brilliance.