Pluto has Dunes

A mountain range on Pluto's Sputnik Planitia ice plain, with dunes in the bottom half of the picture. (Source: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

A new research just published in the journal Science, suggests that this distant world is more dynamic than previously thought. Its atmosphere was believed to be too thin to create dune features. 

The findings come after analyzing Nasa's New Horizons flyby mission of Pluto from July 2015, precisely of a region known as Sputnik Planitia, covered with what appear to be fields of dunes, and lying close to a range of mountains of water ice 5km high called Al-Idrisi Montes. 

In the publication Matt Telfer of the University of Plymouth in England and colleagues explain 357 linear ridges that the planetary scientist interprets as dunes. 

Dunes in Pluto. (Source: NASA/JHUAPL/SwRI)

Relatively strong winds, between about 1 and 10 meters per second, should blow from those mountains across Pluto’s wide plains which are made of nitrogen and methane ice. 

Computer simulations showed 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. 

Instead, little puffs of air coming from Sputnik Planitia’s nitrogen ice as the sun heats it could boost the methane ice particles skyward and into the wind, the team suggests. That process by which solids turn directly into vapor is called sublimation. 

Pluto's atmosphere and haze layers, shot by the New Horizons mission in 2015. (Source: NASA/JHUAPL/SwRI)

The scientists also believe the undisturbed morphology of the dunes and their relationship with the underlying glacial ice suggests the features are likely to have been formed within the last 500,000 years, and possibly much more recently. 

The research was led by scientists from the University of Plymouth (UK), University of Cologne (Germany) and Brigham Young University (USA). 

Sources: Sciencenews, BBC News, University of Plymouth, Science Magazine, Wikipedia