Pluto’s heart-shaped plains are striped with sand dunes, where the sand is made of solid methane ice, a new study finds.
Images from the New Horizons spacecraft’s July 2015 flyby of Pluto show 357 linear ridges that planetary scientist Matt Telfer of the University of Plymouth in England and colleagues interpret as dunes that have been shaped by a novel process, the team reports in the June 1 Science.
The ripples lie parallel to the Al-Idrisi Montes mountain range at the western edge of Sputnik Planitia, the wide plains of nitrogen and methane ice that form part of Pluto’s famous heart-shaped region. Relatively strong winds, between about 1 and 10 meters per second, should blow from those mountains across the plains.
Computer simulations suggest that despite Pluto’s thin atmosphere, these winds are strong enough to keep sand-sized methane ice particles moving once they become airborne. But the winds are probably too weak to lift the grains off the ground in the first place.