Study of Lunar Deep Materials using Clementine UV-VIS Data

我们建立了一种利用克莱门汀号航天器获得的UV-VIS数据估计月球深部内部成分的方法。我们还为Clementine所获得的UV-VIS图像建立了数据库，该系统由一个工作站和一个CD-ROM转换器组成，其中加载了大约100万张Clementine图像。数据库中的图像数据也可以通过计算机网络远程检索。数据库还允许我们搜索和检查位于不同cd - rom中的图像。我们的数据分析系统可以利用头文件中列出的描述航天器位置和姿态的信息，计算出图像中每个像素的经纬度，然后自动将多幅图像拼接成一个大的拼接图，提取出所需的信息。为了从可见红外数据中提取成分信息，地形校正、相位角校正等几何校正是非常重要的。去年的研究表明，如果利用月球地形数据对反射光谱进行地形校正，我们可以在3%的精度内校准反射光谱。我们还表明，相位角（即来自月球表面的入射太阳光与反射光之间的角度）的影响取决于材料和波长。在今年的研究中，我们使用克莱门汀号数据详细研究了相位函数，从而获得了不同相位角下的多光谱图像。通过本研究，我们可以定量地证明相位角对材料和波长的依赖关系。Mare和Highland在相位角为2°时的相函数差为17%，相同条件下415nm到7Sonm的波长差为10%。通过对分析方法的改进，可以比以前更可靠地推断成分或空间侵蚀效应。少

We established a method of estimating the composition of the lunar deep interior using the UV-VIS data obtained by the Clementine spacecraft. We also made a data base for the UV-VIS images obtained by the Clementine, This system consists of a workstation and a CD-ROM changer which is loaded with about one million Clemetine images. The image data in the data base can be retrieved remotely too through computer network. The data base also allows us to search and inspect the images located in different CD-ROMs. With our data analysis system, we can calculate the latitude and longitude of each pixel in an image using the information listed in the header file which describes the position and attitude of the spacecraft, and then we can automatically assemble many images to make a large mosaic and extract the required information.In order to extract information of the composition from the visible-infrared data, geometrical corrections such as those of topographic correction and phase angle cor … More rection are very important. The study made in the last year showed that we can calibrate the reflection spectra within 3% accuracy if the topographic correction on the reflection spectra is made using the lunar topographic data. We also showed that the effect of the phase angle (i.e. angle between the impinging solar light and reflecting light from the lunar surface) depend on the material and wavelength, In this year's study, we investigated in detail on the phase function using the Clementine data which gives us the multi-spectrum images taken at different phase angles. Through this study, we can demonstrate quantitatively the material and wave-length dependence of the phase angle. The compositional difference between Mare and Highland amounts to the difference of phase function of 17% at a phase angle of 2 deg, and the wavelength difference from 415nm to 7Sonm amounts to 10% at the same condition. From these improvement of analysis method, it has become possible to infer the composition or space erosion effect more reliably than before. Less