Fretted Terrain

Explanation: In looking over images of Pluto's informally named Venera Terra region, New Horizons scientists have spotted an expanse of terrain they describe as "fretted." As shown in the enhanced-color image at top, this terrain consists of bright plains divided into polygon-shaped blocks by a network of dark, connected valleys typically reaching a few miles (3 to 4 kilometers) wide. Numerous impact craters of up to 15 miles (25 kilometers) in diameter also dot the area, implying the surface formed early in Pluto's history. New Horizons scientists haven't seen this type of terrain anywhere else on Pluto; in fact, it's rare terrain across the solar system — the only other well-known example of such being Noctis Labyrinthus on Mars.

Pluto

Image credit: NASA/NHUAPL/SwRI