It looks like our moon but this photo is of the planet Mercury taken by the Messenger spacecraft in its recent, first fly-by of the planet nearest the Sun. The robotic spacecraft is scheduled to fly past Mercury twice more before entering orbit there in 2011. The spacecraft already has taken over 1,000 images of the planet and will do many more for future study by planetary geologists. The spacecraft was about 12,000 miles from the planet in this NASA photo.