Experimental demonstration of the role of cohesion in electrostatic dust lofting

Abstract

The cohesion between small dust particles plays an important role in determining the electrostatic force required to loft charged dust off a surface. On airless, celestial bodies, the cohesive bond between dust particles can be stronger than the gravitational force. Assuming that the charge on dust particles is given by Gauss' law, a theoretical model considering both cohesive and gravitational forces has predicted that intermediate-sized particles require the smallest electric field strength to loft. We experimentally confirm that, for a given electric field, intermediate-sized particles are lofted, while smaller and larger particles do not move. Key Points Intermediately-sized dust grains are easiest to electrostatically loft Cohesion drives the electric field required to loft small dust grains in plasma Experiment and theory confirm the importance of cohesion for small grains. ©2013 American Geophysical Union. All Rights Reserved.