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Fragments Delivered by Secondary Craters at the Chang'E‐4 Landing Site
Author(s) -
Ding Chunyu,
Xiao Zhiyong,
Wu Bo,
Li Yuan,
Prieur Nils C.,
Cai Yuzhen,
Su Yan,
Cui Jun
Publication year - 2020
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2020gl087361
Subject(s) - impact crater , regolith , ejecta , geology , astrobiology , projectile , radar , lunar craters , geomorphology , astronomy , aerospace engineering , physics , quantum mechanics , supernova , engineering
The Chang'E‐4 landing site is depleted with boulders seen from both orbit and surface. However, the Yutu‐2 rover came across thousands of concreted fragments in and around an abnormally fresh crater that has more elevated northwestern rims. The origin of the fragments is crucial to resolve the provenances of surface materials detected by the rover. The lunar penetrating radar performed two in‐and‐out scans for the blocky ejecta, revealing that the subsurface materials have indistinguishable radar permittivity with the surrounding regolith. Forward modeling of electromagnetic wave propagation shows that the fragments were not an original component in the subsurface. This crater is among the several fresh craters photoed by the rover, and they are located in an eastern extension ray of the Zhinyu crater. The small craters are likely secondaries of Zhinyu, and the fragments contain a mixture of shattered projectiles and most likely compacted regolith clumps formed during the secondary impacts.