MTE Features of Apollo Basin and Its Significance in Understanding the SPA Basin

Abstract

Apollo basin is located within the large South Pole–Aitken (SPA) basin. The study on Apollo basin will provide interesting information about the basic geologic issues about the lunar farside. In this paper, the normalized brightness $(T_{B})$ temperature $(nT_{B})$ maps and the $T_{B}$ difference $(dT_{B})$ maps are generated with the Chang'E-2 microwave sounder data to study the microwave thermal emission features of Apollo basin. The results are as follows. First, the mare volcanism in Apollo basin is re-understood according to the $nT_{B}$ performances at noon, and they should be originated from the southern part of the Apollo basin and strongly altered by the later impact ejecta. Second, the $nT_{B}$ maps indicate that there exists a special material from Dryden crater to Chaffee crater, whose thickness is more than 31 cm but less than 76.9 cm. Third, the similar $dT_{B}$ performances at 3.0 GHz indicate the homogeneous regolith thermophysical parameters of Apollo basin in the lateral direction. Fourth, the $dT_{B}$ maps and the discovered cold $T_{B}$ anomaly indicate the homogeneity of the SPA basin at least in the microwave thermophysical parameters. Our study also shows that the scientific study about the lunar surface is not sufficient only by visible data.