Dynamic Theory of Charged Dust Grains Above the Lunar Surface

Abstract

The near surface electric field generated on the surface of the Moon causes the
levitation of charged dust grains above the lunar surface. The levitated dust grains
are continuously adjusting their charge distributions with the surrounding plasma to
reach to different levitation heights. This study presents dust levitation mechanism
modeled from Poisson equation for different grain radii at different electron
temperatures. To discuss the dynamical behaviour of lofted dust grains above the
lunar surface, an analytical theory was developed for the first time. The calculation
strongly reflects the dependence of grain radius and electron temperature on
levitation height. During SEPs, at 1000eV ,1µm radius grain was levitated to a
maximum height of 75kmand the same was levitated to a height of 33km at
550eV . Potential profile versus distance from the lunar surface was also studied,
an important consideration for calculating the maximum levitation height for a grain
of specific radius.