Titan dunes

The Cassini spacecraft currently orbiting Saturn has determined that Saturn's largest moon Titan hosts vast, rippled dune fields that encircle the moon near its equator. The dunes are presumed to be the result of global easterly winds and may yet be in the process of forming and eroding today. The dunes may be composed of hydrocarbon sand grains likely derived from organic chemicals in Titan’s atmosphere.

This image suggests how the outer portion of a dune field might appear from Titan's surface.