YEARLY CHANGES IN DUST-DEVIL TRACKS WITHIN MALEA PLANUM, MARS

Malea Planum, Mars (centered at 64.80ºS, 65.00ºE) contains linear-to-sinuous dark lineaments that are interpreted to be dust-devil tracks. To our knowledge, no one has yet systematically examined how dust-devil tracks change from year-to-year in Malea Planum. Preliminary observations of repeated Context Camera (CTX) images, taken at least one Martian year apart, suggest that: dust-devil tracks in Malea Planum disappear in the winter, and in the summer some old tracks reappear while new tracks form; local topography may play a strong role in the location of particular dust-devil tracks; the number of dust-devil tracks per unit area appears to change from year to year; in some sites, the dominant trend of dust-devil tracks appears to be different each year. To test these initial observations, we will create detailed maps of dust-devil tracks found in overlapping CTX images that were collected in different Martian years. To date, we have identified 6 different sites within Malea Planum (each ≥125 km²) that are covered by CTX images that were collected in 2 different Martian years, and 1 site (~70 km²) that was repeatedly imaged by CTX in 3 distinct Martian years. Here, we will present the preliminary results of our mapping and analyses.