Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. Hurtling through space above the Red Planet , potato-shaped Phobos completes an orbit of Mars in less than eight hours. The area imaged is about 250 kilometers across and is seen in panels from left to right as red filter, blue filter, and combined color composite views from the MGS wide-angle camera system. The three dark spots most easily seen in the red image are likely small fields of dark sand dunes on crater floors.
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