Pluto's surface ice. Satellite image showing blocks of the dwarf planet Pluto's water-ice crust (upper left) in the al-Idrisi mountains. Here, several sheer faces appear to show crustal layering, which might be related to the layers seen in some of Pluto's crater walls. The mountains end abruptly at the shoreline of Sputnik Planum (lower right). Imaged by the Long Range Reconnaissance Imager (LORRI) on NASA's New Horizons interplanetary space probe.