Universe Today
A brand new batch of Pluto and Charon photos showed up today on the New Horizons LORRI (LOng-Range Reconnaissance Imager) site. The photos were taken during the close flyby of the system on July 14, 2015 and show rich detail including craters and parallel cracks on Charon and thousands of small pits punctuating Pluto's nitrogen ice landscape. Have at 'em!
The first couple images feature the region informally known as Sputnik Planum. According to a release from NASA today, scientists think the region 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 in Pluto's thin atmosphere. Still, their curious shapes and alignments remain a mystery. Adding to the intrigue is that even when seen up close, no impact craters are visible, testifying to the icy plain's extreme geologic youth.
By the way, there are more images at the LORRI link at top. I picked a representative selection but I encourage you to visit and explore.