Laboratory Investigation of Rate of Electrostatic Dust Lofting Over Time on Airless Planetary Bodies

We present the laboratory results on electrostatic dust lofting rates expected on airless planetary bodies. Dust lofting is shown to be a time‐dependent process that begins at a relatively fast rate on an initialized surface and slows down as time progresses. The slowdown is likely due to the filling of interparticle microcavities as a result of dust movement or the removal of loose upper layers, which reduces the microcavity charging effect. It is suggested that the transient dust lofting rate under the charging conditions at 1 AU may reach several particles·cm−2·s−1 lasting over a short duration. Such intense electrostatic dust lofting could be responsible for transient phenomena such as the lunar horizon glow and could be intermittently sustained by other processes that reinitialize the surface conditions. The average dust lofting rate on a geological timescale is expected to remain low due to the rate decrease over time. Plain Language Summary Recent laboratory results have shown the most convincing evidence in support of the occurrences of electrostatic dust transport on the surfaces of airless planetary bodies. A critical question to assess its relative importance on surface processes is to understand how fast electrostatic dust transport can act. Here we present the laboratory results to estimate electrostatic dust lofting rates expected on airless bodies near 1 AU. We found that dust lofting is a time‐dependent process. It begins relatively fast and slows down as time progresses. The intense lofting rate of dust particles over a relatively short duration in local regions could be responsible for transient phenomena, such as the lunar horizon glow. Such intense rates can be intermittently revived by other processes that reset the surface conditions. Global changes in the regolith properties (e.g., surface morphology and porosity as well as space weathering effects) due to electrostatic dust transport could have a long geological timescale due to the rate decreasing over time. This work is important for understanding a fundamental planetary science question: How has regolith on airless bodies evolved over time. Key Points Electrostatic dust lofting is a time‐dependent process that begins relatively fast and slows down as time progresses The filling or removal of microcavities between dust particles as a result of dust movement reduces the microcavity charging effect The intense dust lofting rate over a short duration could be responsible for transien