NASA's Curiosity rover has certainly been a prolific photographer since landing on the surface of Mars little over a year ago. But recently the rover took a rare look skywards to capture an eclipse of the Sun from the Red Planet using its telephoto camera. During the rover's long trip to the base of Mount Sharp, it took a short break to watch as the larger of Mars' two moons, Phobos, quickly passed overhead. The event's known as a ring — or annular — eclipse, with the edges of the Sun poking out from around the moon, and the shot above is a composite of three pictures taken three seconds apart. Phobos is just about 14 miles in diameter and it's only 3,700 miles from the surface, making it roughly 66 times closer than the Moon is to Earth. It's believed that Phobos and its smaller sister moon Deimos were once asteroids, explaining their irregular shape. A researcher on the project is calling Curiosity's photos of the flyby "by far the most detailed image of any Martian lunar transit ever taken," though its merit is primarily aesthetic, not scientific.

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