Aeolian sediment transport on Io from lava-frost interactions

Surface modification on Jupiter's volcanically active moon, Io, has to date been attributed almost exclusively to lava emplacement and volcanic plume deposits. Here we demonstrate that wind-blown transport of sediment may also be altering the Ionian surface. Specifically, shallow subsurface interactions between lava and Io's widespread sulfur dioxide (SO2) frost can produce localized sublimation vapor flows with sufficient gas densities to enable particle saltation. We calculate anticipated outgassing velocities from lava-SO2 frost interactions, and compare these to the saltation thresholds predicted when accounting for the tenuous nature of the sublimated vapor. We find that saltation may occur if frost temperatures surpass 155 K. Finally we make the first measurements of the dimensions of linear features in images from the Galileo probe, previously termed ridges, which demonstrate certain similarities to dunes on other planetary bodies. Io joins a growing list of bodies with tenuous and transient atmospheres where aeolian sediment transport may be an important control on the landscape. Dunes may form on Jupiter's moon Io. Despite a tenuous atmosphere, interactions between widespread lava and sulfur dioxide frost may produce vapor flows dense enough to mobilize sand grains. Ridge-like features may be evidence of this phenomenon.

Automated summary

This study suggests that surface modification on Jupiter's moon Io may not only be attributed to lava emplacement and volcanic plume deposits, but also to wind-blown transport of sediment. Interactions between lava and sulfur dioxide frost may produce vapor flows dense enough to mobilize sand grains, with saltation potentially occurring if frost temperatures surpass 155 K. Ridge-like features on Io could be evidence of aeolian sediment transport.