Mare Moscoviense (148°E, 27°N) is one of the few large maria on the lunar farside, with the thinnest crust and a positive gravity anomaly. In this paper, the Chang’E-2 Microwave Sounder (CELMS) data was employed to study the microwave thermal emission features of mare basalts in Moscoviense Basin. The time angle and linear interpolation method are used to generate the brightness temperature (TB) maps at noon and night, as well as the TB difference (dTB) map. The obtained important results are as follows. (1) A new geologic map is generated with the TB and dTB maps using the maximum likelihood method, which gives a new expression about the basaltic units in Mare Moscoviense compared to the optical results; (2) the substrate temperature of Moscoviense Basin is likely warmer than what we know; (3) unit Ihtm (a Late (?) Imbrian, mid- to high-Ti, high-Fe basalt) is re-understood as two independent volcanic features with their own fissures; (4) the dTB maps firstly indicate that the depth lunar regolith is homogeneous in the highlands surrounding Mare Moscoviense, at least in the microwave domain, and secondly that there exists a special material bringing about the low dTB anomaly in the shallow layer of the east highlands. The results will be of great significance to better understand the basaltic volcanism of the Moon.

The study of mare basalts in microwave range will be of great significance to better understand the basaltic units with complex surface contaminations, particularly in Mare Nubium. In this article, the China Chang'E-2 Lunar Microwave Sounder data and the generated normalized brightness temperature (nTB) and brightness temperature difference (dTB) maps are employed to evaluate the basaltic units in Mare Nubium. The results are as follows. First, two regions with hot anomaly are found, which is likely brought by the high substrate temperature. The anomaly in central Nubium is extensive in range and high in intensity. Second, the nTB and dTB performances can pursue the mare deposits contaminated by the impact ejecta, which reveals special mare basalt with the thin layer in the southeastern part of Mare Nubium. Third, the nTB and dTB maps indicate the complexity of the mare deposits in Mare Nubium. Fourth, the cold dTB anomaly in the western part is proposed as the floor deposits produced during the formation of the Nubium basin. These unusual findings will be of fundamental significance to better understand the basaltic volcanism and the thermal evolution of the Moon.

The internal structures are the key to understand the surface evolution of the Moon. However, the study of such kind is absent. In this study, the Chang'e-2 microwave radiometer data are employed to explore the internal structures in the highlands of the western lunar farside combined with the FeO+TiO2 abundance data and the rock abundance data. The results are as follows. First, a new view on the cratering mechanism is proposed according to the brightness temperature (TB) performances and the estimated rock abundances in King, Bruno, and Necho craters. Second, the influential mechanism of the rocks on the TB is initially identified by the thermal anomalies at noon and night. Third, a special hidden hot anomaly centered at (109.4°E, 6.9°N) northwest to King crater is revealed by the 3.0 GHz map at noon and night but its causes are still unclear. Fourth, the cause of the belt anomaly from Bruno crater to Necho crater has likely resulted from the impact ejecta of King crater. Finally, the highlands in the study area are divided into four units with distinct TB performances. Generally, the TB maps show a different view compared with the optical and thermal infrared data, which is important to improve understanding the surface evolution of the Moon.

Mare Nubium is one of the most ancient circular impact basins on the Moon with the lava flow units ranging from Imbrian to Eratosthenian In this paper, the China Chang'E-2 lunar microwave radiometer data are employed to evaluate the basaltic units of the Mare Nubium. The results indicate that the relationship between the brightness temperature difference (dTB) performances and the basaltic units is rather weak. Moreover, the low dTB anomaly in the middle-western part is interpreted as the floor deposits produced during the formation of Mare Nubium.

The volume FeO and TiO2 abundances (FTAs) of lunar regolith can be more important for understanding the geological evolution of the Moon compared to the optical and gamma-ray results. In this paper, the volume FTAs are retrieved with microwave sounder (CELMS) data from the Chang'E-2 satellite using the back propagation neural network (BPNN) method. Firstly, a three-layered BPNN network with five-dimensional input is constructed by taking nonlinearity into account. Then, the brightness temperature (TB) and surface slope are set as the inputs and the volume FTAs are set as the outputs of the BPNN network. Thereafter, the BPNN network is trained with the corresponding parameters collected from Apollo, Luna, and Surveyor missions. Finally, the volume FTAs are retrieved with the trained BPNN network using the four-channel T-B derived from the CELMS data and the surface slope estimated from Lunar Orbiter Laser Altimeter (LOLA) data. The rationality of the retrieved FTAs is verified by comparing with the Clementine UV-VIS results and Lunar Prospector (LP) GRS results. The retrieved volume FTAs enable us to re-evaluate the geological features of the lunar surface. Several important results are as follows. Firstly, very-low-Ti (<1.5 wt.%) basalts are the most spatially abundant, and the surfaces with TiO2 > 5 wt.% constitute less than 10% of the maria. Also, two linear relationships occur between the FeO abundance (FA) and the TiO2 abundance before and after the threshold, 16 wt.% for FA. Secondly, a new perspective on mare volcanismis derived with the volume FTAs in several importantmare basins, although this conclusion should be verified with more sources of data. Thirdly, FTAs in the lunar regolith change with depth to the uppermost surface, and the change is complex over the lunar surface. Finally, the distribution of volume FTAs hints that the highlands crust is probably homogeneous, at least in terms of the microwave thermophysical parameters.

To evaluate the availability of the volcanism study, the microwave sounder (Chinese lunar exploration project, a microwave sounder, CELMS) data from Change'E -2 satellite were employed in this study to compare with the geologic results derived from optical data and radar data of Mare Imbrium, which is presented as the long duration and the last extensive phase of lunar volcanism. First, the normalized brightness temperature (T-B) is generated to eliminate its strong latitude-dependent effect, which implies a good correlation with the titanium abundance. Moreover, difference between T-B of the same frequency at noon and that at midnight (dT(B)) is deduced to evaluate the absorption features of the lunar regolith. According to the dT(B) change with frequency, a new geologic perspective is given to Mare Imbrium. The new interpretation map largely agrees with optical results in the regions with high (FeO + TiO2) abundance (FTA), and with the interpretation maps by radar data in the regions with low FTA. The statistical results validate the three-phase volcanism in Mare Imbrium. This study also hints the special importance of the CELMS data in understanding the basaltic volcanism of the Moon.

Von Kármán crater is located in the northwest of the SPA basin on the far side of the Moon. The crater cuts through the shallow crust and has abnormal distribution in mineral composition. Therefore，the study on the microwave emission features of Von Kármán crater will be of great significance for the thermal evolution and magma evolution of the moon. Based on the microwave sounder（CELMS）data from Chang’e-2，the brightness temperature（TB）maps and TB difference（dTB）maps are generated using the time angle analysis and the bilinear interpolation method. Then the microwave radiation characteristics of Von Kármán crater are studied combined with previous geologic results and the composition map via the ArcGIS software. The discoveries are as followings：（1）a high TB anomaly is found in the north of the crater basin，preliminarily identified as high substrate temperature；（2）the TB shows a good correlation with the（FeO+TiO2）content in the south part of the crater basin；（3）according to the TB behaviors of the Von Kármán crater，new geological units are zoned in the crater floor;（4）according to the TB performances of the Von Kármán crater，high priority of the candidate landing areas should be given to the north part with TB anomaly，followed by the south and west parts.

Chang’e-4 (CE-4) probe will achieve the first soft landing on the farside of the moon in the history of mankind, and the landing zone is tentatively fixed in the Von Karman impact crater which is in the South Pole-Aitken basin. In view of the lack of field analysis of microwave radiation brightness temperature, analyzed the brightness temperature’s temporal and spatial distribution characteristics of Von Karman impact crater was analyzed based on the field and the penetrability of Chang’e Microwave radiometer. The results show that there is a significant couple mode between 3GHz diurnal brightness temperature field and 37GHz diurnal brightness temperature field, ,and the trend of brightness temperature appeared consistent in the crater. It also turns out that the area with high FeO+TiO2 (FTA) content has a higher relativity , which is the key area of brightness temperature change. Nevertheless, the FTA content does not have significant impact on the density of contours. Contrarily, the density of contours is mainly influenced by the roughness of the moon’s surface. Finally, the research provided a reference for the choice of landing zone of CE-4 probe by analyzing the temporal and spatial distribution characteristics of brightness temperature, stratigraphic unit, chemical constituents of substance and other factors in Von Karman impact crater.