Detail: Pluto "dark areas"

Detail: Pluto "dark areas"
Detail: Pluto "dark areas" Detail from this Pluto mosaic showing a 350-kilometer wide region on Pluto at the boundary between dark-toned, heavily cratered terrain (bottom) and smooth, flat plains (top). Up close, there are areas of lineated terrain that "resemble dunes" but "its origin is under debate." NASA / JHUAPL / SwRI