Speaker
Dr
Sebastien Hess
(ONERA)
Description
Activity: GSP
Contractor(s): ONERA, Lancaster University, Leuven University, Stuttgart University
Technical Officer: Fabrice Cipriani
Summary:
The Apollo missions demonstrated that the lunar regolith, composed of very small dusts of micron to sub-micron sizes, is a potential threat to any mission on or close to the moon surface. The lunar dusts are highly adhesive due to their small size and their electrostatic charge. These dusts are also highly abrasive, so that friction with surfaces can wear down materials and reduce material lifetimes. Dusts also pose a potential health hazard to astronauts. The electrostatic charging of the lunar dusts is suspected to be a key ingredient of the observation of dust “levitation” above the lunar surface and of the formation of a dust haze that may extend to several tens of kilometers in altitude.
Using the Spacecraft Plasma Interaction Software (SPI), we investigate the dust charging on the lunar and asteroid soils, their emission and their dynamics in the plasma. This implies the determination and implementation of a model of the photo-electron sheath above the irregular lunar surface, of a model of the dust charging and emission, and of a model of the dust coupling with the plasma. We present these models and their implementation, as well as the results we obtained concerning the emission and dynamics of the dusts above the asteroid and lunar surfaces, for different solar zenith angle.
