Rock Fragments in Shallow Lunar Regolith: Constraints by the Lunar Penetrating Radar Onboard the Chang'E-4 Mission

Ding, Chunyu1; Xiao, Zhiyong2,3; Wu, Bo4; Li, Zhaojin4; Su, Yan5,6; Zhou, Bin7,8; Liu, Kaijun1; Cui, Jun2,3

2021-09-01

10.1029/2021JE006917

JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS   影响因子和分区

2169-9097

2169-9100

It is generally believed that the top centimeters of mature lunar regolith should be dominated by fine particles that contain few rocky fragments, but surface fragments are occasionally visible in mature lunar regolith. Based on amplitudes of surface echoes received by the Lunar Penetrating Radar onboard the Yutu-2 rover of the Chang'E-4 mission, we extracted regions with abnormally high relative permittivity that is larger than 4, quantifying the abundance of dense fragments within the top similar to 4 cm of the mature regolith along the rover path. We carried out high-resolution numerical simulations for the propagation of electromagnetic waves, showing that the abnormally high relative permittivity is not caused by local topography but due to the existence of dense materials. Using high-resolution images obtained by the panorama camera onboard the rover, we performed correlated observation for areas with abnormally high relative permittivity, confirming that some of these dense materials are exposed rocky fragments. However, most of the high relative permittivity areas are not correlated with surface fragments, and some are located beneath floors of highly degraded small impact craters. We found that regolith clumps formed due to impact compaction are not dense enough to cause the abnormally large relative permittivity. Alternatively, the detected dense materials may be melt-bearing impact breccias in the shallow regolith, which were formed by the host craters. The results revealed a highly heterogeneous structure at shallow depths of mature lunar regolith, revealing a new mechanism of sand-blasting impacts on the destruction of pores in mature lunar regolith.

Moon regolith relative permittivity impact craters Chang'E-4 lunar penetrating radar

SCI

英语

第一 ; 通讯

B-type Strategic Priority Program of the Chinese Academy of Sciences[XDB41000000] ; National Natural Science Foundation of China[42004099,41773063] ; Opening Fund of the Key Laboratory of Lunar and Deep Space Exploration[LDSE202005] ; Key Research Program of Frontier Sciences of Chinese Academy of Sciences[QYZDY-SSW-DQC028] ; pre-research Project on Civil Aerospace Technologies - Chinese National Space Administration["D020201","D020202"] ; Research Grants Council of Hong Kong[R5043-19] ; Shenzhen Municipal Government Investment Project[2106-440300-04-03-901272]

Geochemistry & Geophysics

Geochemistry & Geophysics

WOS:000702402500002

AMER GEOPHYSICAL UNION

SPACE SCIENCE

Web of Science

1.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen, Peoples R China
2.Sun Yat Sen Univ, Sch Atmospher Sci, Planetary Environm & Astrobiol Res Lab, Zhuhai, Peoples R China
3.Chinese Acad Sci, Ctr Excellence Comparat Planetol, Hefei, Peoples R China
4.Hong Kong Polytech Univ, Planetary Remote Sensing Lab, Dept Land Surveying & GeoInformat, Hong Kong, Peoples R China
5.Chinese Acad Sci, Natl Astron Observ, Key Lab Lunar & Deep Space Explorat, Beijing, Peoples R China
6.Univ Chinese Acad Sci, Beijing, Peoples R China
7.Chinese Acad Sci, Key Lab Electromagnet Radiat & Detect Technol, Beijing, Peoples R China
8.Chinese Acad Sci, Aerosp Informat Res Inst, Beijing, Peoples R China

Ding, Chunyu,Xiao, Zhiyong,Wu, Bo,et al. Rock Fragments in Shallow Lunar Regolith: Constraints by the Lunar Penetrating Radar Onboard the Chang'E-4 Mission[J]. JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS,2021,126(9).

Ding, Chunyu.,Xiao, Zhiyong.,Wu, Bo.,Li, Zhaojin.,Su, Yan.,...&Cui, Jun.(2021).Rock Fragments in Shallow Lunar Regolith: Constraints by the Lunar Penetrating Radar Onboard the Chang'E-4 Mission.JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS,126(9).

Ding, Chunyu,et al."Rock Fragments in Shallow Lunar Regolith: Constraints by the Lunar Penetrating Radar Onboard the Chang'E-4 Mission".JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS 126.9(2021).