Dunes on Pluto

When the New horizon spacecraft passed the dwarf planet Pluto (and its twin Charon plus their moons Styx, Nix, Kerberos, and Hydra) it found an alien world.
The surface of Pluto is more geologically diverse and dynamic than had been expected, but the role of its tenuous atmosphere in shaping the landscape remains unclear. The surface of Pluto, as revealed by New Horizons, is diverse in its range of landforms, composition, and age. One of the largest features, Sputnik Planitia, is a plain of frozen nitrogen (N2), carbon monoxide (CO) and methane (CH4), that extends across Pluto’s tropics and at its widest point covers 30° of longitude. New Horizons found extensive dunes on Sputnik Planita[1].

Scientists domonstrated that the wavelength of the dunes (~0.4 to 1 kilometer) is best explained by the deposition of sand-sized (~200 to ~300 micrometer) particles of methane ice in moderate winds (<10 atmosphere="" been="" blown="" by="" could="" down="" from="" grains="" have="" ice="" into="" lofted="" melting="" meters="" methane="" mountains.="" nearby="" nitrogen="" of="" or="" per="" second="" surrounding="" the="">
The undisturbed morphology of the dunes, and relationships with the underlying convective glacial ice, imply that the dunes have formed in the very recent geological past[2]. Remember, in geological terms, 'very recent' means less that 500,000 years.

[1] Telfer et al: Dunes on Pluto in Science – 2018. See here.
[2] McKinnon et al: Convection in a volatile nitrogen-ice-rich layer drives Pluto’s geological vigour in Nature – 2016

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