Topographic Evolution of Von Kármán Crater Revealed by the Lunar Rover Yutu‐2

Abstract

Chang'e‐4 (CE‐4) achieved the first farside landing in Von Kármán crater. In the landing site, linear features have been identified previously from SLDEM and considered to be ejecta from the neighboring Finsen crater. The 5 cm grid spacing digital elevation model of the landing site, generated from the rover's panoramic images, provides more details of the rugged terrain. We further interpret the superimposition of NE‐SW ejecta from Finsen crater on the underlying SE‐NW dome‐like surface relief from Alder crater. The landing site is ~70 m higher than the mare basalts within Von Kármán crater. Numerical simulations predict ~30 and ~35 m ejecta deposited at the landing site from Finsen and Alder craters, respectively. The good agreement between the digital elevation model data and ejecta predicted thickness reveals the topographic evolution of Von Kármán crater, indicating that the rover‐measured material is excavated from Finsen crater with possible contributions from Alder crater.

Geospatial technologies for Chang’e-3 and Chang’e-4 lunar rover missions

“…The mapping and localization products have also been frequently used to support various scientific investigations before and during the missions, e.g. to support data acquisition and analysis by other science instruments, such as the Visible and Near-Infrared Imaging Spectrometer (VNIS) and the Lunar Penetrating Radar (LPR) for investigations of mineralogical compositions and subsurface structures, respectively (Xiao et al 2015;Di et al 2016;Gou et al 2019;Di et al 2019b). Figure 2 shows the technical framework of the geospatial technologies developed and applied in CE-3 and CE-4 missions.…”

“…The DEM and DOM have been used in topographic characterization (e.g. slop and crater distributions) of CE-3 and CE-4 landing sites (Wu, Hu, and Guo 2014;Di et al 2019b;Di, Liu, and Liu 2019c;Zhao, Li, and Wu 2019). CE-2 orbiter acquired 1.5-m resolution images at the pre-selected CE-3 landing site (40°N~50°N, 18°W 35°W).…”

“…Technical framework of the geospatial technologies and applications in CE-3 and CE-4 missions. clusters and ejecta materials which can be traced back to several craters in the vicinity (Di et al 2019b;Di, Liu, and Liu 2019c). In addition to applications in landing site characterization, this high-resolution DOM, along with CE-2 DOM, has been used as a basemap in lander localization and long-term rover traverse planning (Di, Liu, and Liu 2019a;Liu, Di, Li, 2019).…”

“…Figures 9 and 10 reveal that in finer resolution the terrain of CE-4 landing site is much rugged and is generally higher in the NE than in the SW. This DEM contributed to the study of the topographic evolution of Von Kármán crater (Di et al 2019b), which is significant to understanding the origin of the surface material measured by Yuyu-2 rover Gou et al 2019).…”

“…The Yutu-2 rover was successfully released from the lander and touched on the lunar surface on the same day. The success of CE-4 marks the first soft landing of human spacecraft on the far side of the moon and provides a unique opportunity for in-situ exploration of the SPA basin which is the oldest and largest impact basin on the moon (Jia et al 2018;Huang, Xiao, and Flajault 2018;Wu, Li, and Zuo 2019;Di, Liu, and Liu 2019a;Di et al 2019b). As of 4 December 2019, the rover has traversed 345.059 m (odometer reading) (China Daily 2019).…”