Study of Lunar Deep Materials using Clementine UV-VIS Data

我们建立了一种利用Clementine航天器获得的UV-Vis数据来估计月球深部内部成分的方法。我们还制作了Clemetine获得的UV-Vis图像的数据库，该系统由一个工作站和一个装载了约100万张Clemetine图像的CD-ROM转换器组成。数据库中的图像数据也可以通过计算机网络远程检索。该数据库还使我们能够搜索和检查位于不同光盘中的图像。在我们的数据分析系统中，我们可以利用头文件中描述航天器位置和姿态的信息来计算图像中每个像素的经纬度，然后可以自动拼接多幅图像进行大拼接并提取所需的信息。为了从可见光红外数据中提取合成信息，需要从可见光红外数据中提取组成信息，如地形校正和相角校正…等几何校正更多的纠正是非常重要的。过去一年的研究表明，如果利用月球地形数据对反射光谱进行地形改正，可以在3%的精度内对反射光谱进行标定。我们还发现，位相角(即入射太阳光与月球表面反射光之间的角度)的影响与材料和波长有关，在今年的研究中，我们利用Clementine数据详细研究了位相函数，给出了在不同相角下拍摄的多光谱图像。通过这项研究，我们可以定量地证明相角与材料和波长的关系。在2°的相位角下，MARE和Highland的组成相差17%，415 nm到7Sonm的波长相差10%。通过这些分析方法的改进，可以比以前更可靠地推断成分或空间侵蚀效应。较少

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