On the Fluxes of Dust Particles Detected near the Lunar Surface by the Chang’e 3 Lander

We analyze the origin of dust particles in the near-surface layer of the Moon, the fluxes of which were measured in the Chang’e 3 lunar mission carried out by the People’s Republic of China (PRC). We consider the lunar regolith particles rising above the lunar surface due to either electrostatic processes or impacts of meteoroids. It turns out that the main contribution to the observed mass fluxes of dust was made by micron-size dust particles, which originate from the regolith matter ejected from the lunar surface due to meteoroid impacts. We perform theoretical calculations of the mass flux of dust particles accumulated on the measuring surface of the Chang’e 3 lander, which is at a height of 190 cm above the lunar surface. The result is that the theoretical estimate is roughly seven times higher than the value of the dust mass flux measured in the course of the Chang’e 3 mission. This disagreement may be caused by both (i) the inaccuracy in the parameters used in calculations to characterize the conditions on the Moon and the properties of the lunar regolith and (ii) the fact that the main mass of dust rising above the lunar surface due to meteoroid impacts is contained in micron-size particles, a significant portion of which could crumble from the measuring surface of the Chang’e lander and, consequently, was not covered by the measurements.