Speaker
Description
Modification of thermal control surfaces due to lunar dust remains uncertain for upcoming lunar missions. While dust deposition rates have been both estimated and measured, significant uncertainties persist. Prior studies established that there is a clear link between lunar dust simulant (LDS) coverage to changes in solar absorptivity (α) and infrared emissivity (ε) of radiator.
However, there are no measurement-based correlations directly connecting dust deposition rates (µg/cm²/year), dust coverage (%) and modifications in α and ε. In an ESA-funded experiments by ONERA 20 thermal control coatings were tested, with varying LDS levels, establishing correlations between dust coverage, deposition, and modification factors.
Utilizing these measurements, an empirical methodology was developed to correlate measurement data from the Lunar Dust Simulator (LDS) with actual lunar dust, taking into account differences in parameters such as density, thermo-optical properties, dust grain morphology, and particle size distribution. This approach enabled the derivation of empirical equations applicable to each of the 20 thermal control surfaces, quantifying how contamination by lunar dust—expressed as mass or deposition rate—impacts their thermo-optical characteristics.
