Martian dust storm activity near the Mars 2020 candidate landing sites: MRO-MARCI observations from Mars years 28–34

Abstract

MRO-MARCI daily global mapping images from 16 November 2006 (Ls = 111.4°) through 15 July 2017 (Ls = 33.5°), covering portions of seven consecutive Martian years (MY 28 – MY 34), were used in a survey of dust storm activity within 2000 km radius of the final three candidate sites for the 2020 Mars Rover mission (Columbia Hills at 14.59° S 175.53° E, North East Syrtis at 17.89° N 77.16° E, and Jezero at 18.39° N 77.54° E). A total of 1321 dust storms (1228 local, 93 regional) were observed. Storms were observed in all seasons, but showed distinct seasonal trends. Columbia Hills monitoring area experienced eastward traversing polar hood/seasonal cap edge storms during southern autumn and winter, with a gradual transition during southern spring to northern hemisphere storms along the Elysium and Arcadia-Amazonis tracks with winter dominated by the northern hemisphere storms. Syrtis sitess were dominated by cap edge storms during northern spring, transitioning to subtropical (Syrtis Major and north of Hellas Basin) storms in both hemispheres during northern summer, with autumn bringing continued storm activity in the southern subtropics and increased activity along the Utopia cross-equatorial storm-track, followed in winter by a transition back to north polar hood/seasonal cap edge storms. Peak storm frequency occurs during autumn for the Syrtis sites and winter for Columbia Hills site.During the entry, descent, and landing (EDL) season, Ls = 345–25°, the daily probability of dust storm activity at the landing sites ranged from ≤ 1.6% for the Columbia Hills to ≤ 3.2% for Syrtis sites. For EDL sol (Ls ∼ 6°), storm probabilities drop to approximately 0.0% for Columbia Hills and ranged from 0.6–1.2% for the other sites, indicating that storms are of minimum concern for EDL.