基于“嫦娥2号”CELMS数据的冯·卡门撞击坑微波辐射特性

Microwave Emission Features of Von Kármán Crater Revealed by Chang'E-2 CELMS Data

冯·卡门(Von Kármán)撞击坑位于月球背面的SPA盆地西北部,切穿了浅层月壳,具有异常的矿物成分分布。基于微波辐射计数据的月壤微波辐射特性分析,对月球热演化和岩浆演化研究具有重要的参考价值。本研究基于"嫦娥2号"卫星微波辐射计数据,采用时角分析、双线性插值方法,生成了研究区域的亮温(T_B)图和亮温差(dT_B)图像;结合Arcgis软件,叠加地质图,并结合成分、地形图,研究了Von Kármán撞击坑微波辐射特性。研究结果表明:研究区北部出现高T_B异常,初步判定为下垫面温度较高;研究区南部出现与钛铁矿(FeO+TiO_2)含量分布相对应的亮温表现;结合研究区的微波辐射特性,重新进行了冯·卡门撞击坑地质解译;根据冯·卡门撞击坑的亮温表现,建议北部为着陆区重点选择区,其次为南部和西部。

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.