中文摘要：

提出了一种应用着陆器降落相机序列图像和嫦娥二号数字正射影像（DOM）的嫦娥三号着陆点位置评估方法.以高分辨率降落图像上的着陆器位置为基础,通过降落序列图像间的尺度不变特征转换（SIFT）匹配,计算序列图像间的几何转换参数,完成着陆器在低分辨率降落图像上的定位.并通过提取降落图像与嫦娥二号DOM影像上的撞击坑,实现图像间的匹配与几何转换参数的计算,最终得到着陆器在嫦娥二号DOM影像上的位置.通过对比美国“月球勘测轨道器”（LRO）拍摄到的着陆器真实位置,验证了定位方法的有效性,其定位精度在DOM影像1个像素以内.

英文摘要：

This paper proposes position precision evaluation method of Chang＇e-3 landing point based on descent sequence images and Chang＇e-2 DOM（Digital Orthoimage Map）. Firstly, the landing position of Chang＇e-3 is manually determined on the descent image with highest resolu- tion, and then transferred to other descent images by the geometry relationship established through SIFT matching among descent images. Secondly, lunar crater extraction method, implemented by mean-shift image segmentation, is applied to the registration of low resolution descent image and Chang＇ e-2 DOM. Consequently, the landing position is transferred to Chang＇ e-2 DOM. The localization accuracy is higher than a pixel of Chang＇e-2 DOM, and is verified by the landing position observed by the LRO image.