boundless-science: Methane ice dunes found on PlutoThe findings come after images from NASA’s New
boundless-science: Methane ice dunes found on Pluto The findings come after images from NASA’s New Horizon mission have been analysed from travelling the system for nearly a decade. As well as having a diameter of only 2,377km and surface temperatures of -230C; Pluto’s atmosphere was thought to be too thin for the formation of features similar to those found in deserts on earth. The dunes formed next to a major mountain range of water ice 5km high where wind is generated as air flows downhill. It can get as high as 10m/s which is enough to carry the tiny particles. Scientists can’t see everything from the images but they were able to discern the dunes are 0.4-1km apart and the methane crystals 200-300 micrometers in diameter (roughly a grain of sand). The grains of methane (and maybe nitrogen) are thought to be produced through a process known as sublimation. This is where a solid transitions directly to a gas skipping the liquid phase. This essentially transports it into the atmosphere where the tiny crystals form then the Pluto’s winds move them around the dwarf planet. -- source link