A Novel Triangulated Spherical Brightness Temperature Model of the Moon With Chang’e-2 Microwave Radiometer Data

With the continuous advancements in the Chinese lunar exploration program, the substantial brightness temperature (TB) data acquired by the Chang’e (CE) orbiter series have provided unprecedented opportunities for studying the geology of the Moon. In particular, the TB data obtained by the CE-2 mission have offered a new observational perspective for investigating the geological characteristics of the Moon. In this article, we propose a novel triangulated spherical technique for constructing a TB model of the Moon with CE-2 microwave radiometer (MRM) data. Specifically, we directly parameterize spherical TB data based on spherical area coordinates and use spherical Bézier surfaces to capture the TB distributions for daytime and nighttime across different frequency channels. This model is enabled by the theoretical characterization of spherical data, which allows us to construct geometric formulations that parameterize the entire TB data of the Moon. It incorporates an octahedral partitioning strategy and divides the lunar surface into eight regions, each undergoing iterative refinement to enhance precision through detailed analysis. Furthermore, the spherical Bézier surfaces effectively mitigate the complexity of structural components on TB estimations. Experimental results demonstrate that the proposed TB model of the Moon significantly outperforms existing approaches in characterizing the lunar TB distribution, providing important application in analyzing the geological features and thermal processes of the Moon.