NASA’s New Horizons spacecraft provides us with an up-close look at Pluto’s largest moon, Charon. This footage was captured on July 13, 2015, from a distance of 289,000 miles (466,000 kilometers), and was combined with color information obtained by New Horizons’ Ralph instrument on the same day. The marking you see in Charon’s north polar region is a thin deposit of dark material over a distinct, sharply bounded, angular feature. Continue reading for another video and more information.
“We know that Charon’s surface is too cold for anything other than solids to exist, and the surface isn’t subject to extreme changes in temperature and/or pressure, so it is unlikely significant phase transitions are occurring. Instead, we think that the color variation is due to a change in surface composition, which leads to the conclusion that the surface of Charon�s northern polar region is made up of different material than the rest of Charon,” reports NASA.