Thermal Modeling of the Lunar Regolith at the Chang'E-4 Landing Site

Abstract

Accurate assessments of surface temperatures on the Moon are important for understanding the physical properties of the lunar surface regolith and thermal effects on the reflectance spectra beyond 2 μm. The local time resolved spectral measurements of the same region were used to estimate the surface temperature at the Chang'E-4 landing site. The results show that the surface temperatures at the landing site at lunar local time 14:28–14:41 are 346 ± 8 K. The spectral absorptions at ∼2 μm of the lunar surface are overestimated without sufficient thermal removal, and consequently may have resulted in overestimation of pyroxene and/or glasses at the landing site. The results play a foundation for correcting thermal effects of reflectance data that will be acquired by Chang'E-5 and -6 and possible other future Chang'E missions.