Measurements of electrical discharges in Martian regolith simulant

Due to the prevalence of Martian dust devils and dust storms, an understanding of the underlying physics of electrical discharges in Martian dust is critical to future Mars exploratory missions. Measurements on the charging of single dust grains show that particles of Martian regolith simulant can have large electric potentials due to triboelectric charging. As a result of this charging, agitated Martian regolith simulant in a low-pressure CO₂ atmosphere produces electrical discharges. Under extremely dark viewing conditions, electrical discharges are visually observed at pressures between 0.1 and 50 torr. Measurements of the frequency and intensity of these discharges as a function of pressure (from 0.1 to 5 torr) and stirring speed (corresponding to wind speeds from 0.1 to 2.6 m/s) show that discharges occur at pressures and wind speeds similar to those expected on the Martian surface