Pluto has dunes of solid methane

Spanning 47 miles across the boundary of an ice plain called Sputnik Panitia, the rippling methane dunes can be seen pushing up against mountains on the freezing planet, which has an average surface temperature of -230C. 

Following an analysis of the shape and size of the dunes, and nearby wind streaks on Pluto’s surface, scientists concluded solid nitrogen converting directly into gas, known as sublimation, likely released sand-sized grains of methane directly into the atmosphere. They were then blown by Pluto’s thermal winds across the ice plane and settled at the bottom of the mountain range. The researchers concluded the dunes were probably formed in the last 500,000 years, and possibly much more recently, due to the fact they were largely undisturbed. 

https://www.independent.co.uk/news/science/pluto-methane-dunes-ice-mountain-range-nasa-new-horizons-spacecraft-a8377746.html