The Lobachevsky Anomaly in HR (context image from AS 16-121-19407)

An oblique view looking North-West at part of the wall of the crater Lobachevsky on the Lunar Far (or Dark) Side. It shows a small crater on Lobachevsky's wall with unusual streaks of dark material that appear to have originated from the lower rim of the structure and to have moved down toward the floor of Lobachevsky. This feature was first noticed by T. K. Mattingly, the Apollo 16 CMP, who described the darker streaks as probable lava flows (Mattingly, El-Baz, and Laidley, 1972).
However, the streaks can also be explained by the downslope movement of dark fragmental debris excavated from Lobachevsky's wall by the small crater. Closer to the lower border of the photograph is a bright area extending across Lobachevsky's rim. This area and other sinuous light-colored markings in the upper half of the photograph are on the periphery of an enormous field of light-colored swirls in this part of the Far-Side (El-Baz, 1972a).
The origin of the swirls is not well understood.