Saturn's largest moon, Titan, may have extremely violent methane storms, which may solve the mystery about the direction of the moon's dunes.
With its thick, hazy atmosphere and surface rivers, mountains, lakes and dunes, Titan, Saturn's largest moon, is one of the most Earth-like places in the solar system.
As the Cassini-Huygens spacecraft examines Titan over many years, its discoveries bring new mysteries. One of those involves the seemingly wind-created sand dunes spotted by Cassini near the moon's equator, and the contrary winds just above.
The direction of the dunes has at times been attributed to the effects of Saturn's gravitational tides or various land features or wind dynamics, but none quite explained their eastward slant.
Violent methane storms high in Titan's dense atmosphere, where winds do blow toward the east, might be the answer, according to new research by University of Washington astronomer Benjamin Charnay and co-authors.
Using computer models, Charnay, a UW post-doctoral researcher, and co-authors hypothesize that the attitude of Titan's sand dunes results from rare methane storms that produce eastward gusts much stronger than the usual westward surface winds.
The study is published in the journal Nature Geoscience.