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P-29521 BW Range: 557,000 kilometers ( 346, 000 miles) The southern hemisphere of Umbriel displays heavy cratering in this Voyager 2 image. This frame, taken through the clear-filter of Voyager's narrow-angle camera, is the most detailed image of Umbriel, with a resolution of about 10 km (6 mi). Umbriel is the darkest of Uranus' larger moons and the one that appears to have experienced the lowest level of geological activity. It has a diameter of about 1,200 km (750 mi) and reflects only 16 percent of the light striking its surface; in the latter respect, Umbriel is similiar to lunar highland …
