Solar Panel Clearing Events, Dust Devil Tracks, and in-situ Vortex Detections on Mars.

Spirit rover solar array data, which if publicly-archived would provide a useful window on Mars meteorology, shows dust-clearing events coinciding with the onset of dust devil season in three Mars years. The recurrence interval of 100-700 days is consistent with the extrapolation of Pathfinder and Phoenix vortex encounters indicated by pressure drops of ~6-40 Pa (similar to laboratory measurements of dust lifting threshold) and with observed areas and rates of generation of dust devil tracks on Mars.