A view of Umbriel from Voyager 2 in 1986. Thanks to Ted Stryk who specializes in re-imaging images from old missions with today’s advanced computing. There are few images of this place and no missions planned any time soon… so these may be all we ever see of it in our lifetime.
The most interesting detail revealed in these images is the bright white disk that appears at the top of this image which is actually at the equator. Since the Uranian system is turned on its side almost 90 degrees to the rest of the solar system, Voyager passed all of its moons at nearly the same time. The orientation means we are actually seeing the southern pole nearly straight on in both these images. Such an unusually high-contrast feature reminds one of Saturn’s strange moon Iapetus. It could be the same phenomenon that made Iapetus look the way it does may have also been at work on Umbriel.