An Improved Digital Elevation Model of the Lunar Mons Rümker Region Based on Multisource Altimeter Data

Fei Li,Qing Cheng,Weifeng Hao,Jean-Pierre Barriot,Chang Zhu,Mao Ye,Jianguo Yan,Tao Sun

doi:10.3390/rs10091442

Abstract

Mons Rümker is the primary candidate region for the lunar landing mission of Chang’E-5. We propose a data processing method that combines multisource altimeter data and we developed an improved digital elevation model (DEM) of the Mons Rümker region with a horizontal resolution of 256 pixels per degree. The lunar orbiter laser altimeter (LOLA) onboard the lunar reconnaissance orbiter (LRO) acquired 884 valid orbital benchmark data with a high precision. A special crossover adjustment of 156 orbital profiles from the Chang’E-1 laser altimeter (LAM) and 149 orbital profiles from the SELenological and ENgineering Explorer (SELENE) laser altimeter (LALT) was applied. The radial residual root mean square (RMS) of the LAM was reduced from 154.83 ± 43.60 m to 14.29 ± 27.84 m and that of the LALT was decreased from 3.50 ± 5.0 m to 2.75 ± 4.4 m. We used the adjusted LAM and LALT data to fill the LOLA gaps and created the merged LOLA + LAM and LOLA + LALT DEMs. The merged LOLA + LAM DEM showed distortions because of the horizontal geolocation errors in the LAM data. The merged LOLA + LALT DEM was closer to the ground truth than the LOLA-only DEM when validated with the images of the LRO camera (LROC).

Highlights

The Mons Rümker region is centered at 301.9◦E, 40.7◦N and is comprised of a plateau with an area of ~4000 km2
Over the last ten years, the knowledge of lunar topography has greatly improved because of the SELenological and ENgineering Explorer (SELENE) mission, the Chang’E-1 (CE-1) mission, and the lunar reconnaissance orbiter (LRO), all of which carried laser altimeters [9,10,11]; new global lunar digital elevation model (DEM) have been produced with a variety of resolutions and accuracies
We examined the LRO camera (LROC) image of the Louville–K crater (Figure 10d) and the visual examination suggests that the merged laser altimeter (LALT) + lunar orbiter laser altimeter (LOLA) DEM is closer to the ground truth

Summary

Introduction

The Mons Rümker region is centered at 301.9◦E, 40.7◦N and is comprised of a plateau with an area of ~4000 km. Mons Rümker is the primary candidate for the landing region of the Chang’E-5 lunar sample return mission and an accurate digital elevation model (DEM) is indispensable for selecting and assessing the landing site [1,2]. The Apollo 15 to Apollo 17 missions provided preliminary laser altimeter data for creating maps of the lunar topography [7]. Over the last ten years, the knowledge of lunar topography has greatly improved because of the SELenological and ENgineering Explorer (SELENE) mission, the Chang’E-1 (CE-1) mission, and the lunar reconnaissance orbiter (LRO), all of which carried laser altimeters [9,10,11]; new global lunar DEMs have been produced with a variety of resolutions and accuracies

Methods

Findings

Discussion

Conclusion