Within the frame of future lunar missions, the evaluation of the change in the performance of representative covering materials is required to estimate the effect of particulate contamination induced by the dust coverage over time (natural or man-induced).

It was previously demonstrated that “even small sub-mono layers of lunar dust (simulant material) increased the absorptivity of white paint and second surface mirrors significantly” [Gaier 2008 - NASA/TM—2008-215492].

This paper reports on the characterization of the degradation of thermal and power functional surfaces properties due to LHS-1 deposits (lunar dust simulant –LDS from Exolith).

A set of more than 20 different materials (Coverglasses, Optical Solar Reflectors, Second Surface Mirrors, white and black paintings, MLI outer layers...) have been tested with various levels of dust coverage.

The large available set of data allows for highlighting the main trends in response of emissivity and solar absorptance as a function of dust coverage.

Globally, the evolution of emissivity with percentage of coverage is compliant with the “rule of mixture” model (combination of LDS and substrate responses proportionally to the ratio of the covered and uncovered surface areas, [Gaier 2008]). The response of solar absorptance is not straightforward: depending on the substrate a linear, exponential or polynomial fit can be used. The approach to measure the LDS thermo-optical properties is questioned. Finally, a metric is proposed to link dust coverage to degradation of solar absorptance and emissivity for all tested material families.