Abstract

Orbital and surface observations demonstrate that aeolian activity is occurring on Mars. Here we report the aeolian changes observed in situ by NASA's InSight lander during the first 400 sols of operations. Aeolian changes include creep of grains with diameters of up to 3 mm, dust removal, dark trails left by passing vortices and possible saltation. InSight has observed such changes by using, for the first time, simultaneous imaging and continuous, high-frequency meteorological, seismological, and magnetic measurements. We show that this multi-instrument combination constrains both the timing, and specific atmospheric conditions during which, aeolian changes occur. The observed changes are infrequent and episodic, consistently occur between noon and 3 pm, and are systematically associated with the passage of convective vortices. The sudden onset of peak vortex wind speeds promotes particle motion during sequences of enhanced vortex activity and stronger ambient winds. Aeolian changes are correlated with excursions in ground acceleration and magnetic field strength, suggesting vortex-induced ground deformation and charged-particle motion.