Pluto’s Puzzling Patterns and Pits
http://www.nasa.gov/nh/pluto-puzzling-patterns-and-pits
Now this latest image, from the heart of Pluto’s heart feature, show the plains’ enigmatic cellular pattern (at left) as well as unusual clusters of small pits and troughs (from lower left to upper right).
Scientists believe that this area, informally known as Sputnik Planum, is composed of volatile ices such as solid nitrogen. They theorize that the pits and troughs – typically hundreds of meters across and tens of meters deep – are possibly formed by sublimation or evaporation of these ices. However, the reasons for the striking shapes and alignments of these features are a mystery. Adding to the intrigue is that even at this resolution, no impact craters are seen, testifying to the extreme geologic youth of Sputnik Planum.
This image was taken by the Long Range Reconnaissance Imager (LORRI) on NASA's New Horizons spacecraft shortly before closest approach to Pluto on July 14, 2015; it resolves details as small as 270 yards (250 meters). The scene shown is about 130 miles (210 kilometers) across. The sun illuminates the scene from the left, and north is to the upper left.