astroengine writes "Dust devils are a well-known atmospheric phenomena on Mars, and as these new HiRISE observations show, the devilish vorticies can carve beautiful patterns in the Martian dust. What's more — in side-by-side comparisons of observations of the same Mars region years apart — it appears that the active Mars atmosphere acts like an Etch A Sketch, rubbing out the dust devils' tracks, only for the dust devils to make brand new tracks years later."
