Compositional variations along the route of Chang’e-3 Yutu rover revealed by the lunar penetrating radar

Progress in Earth and Planetary Science

Yan Su¹  Zhiyong Xiao²  Chunyu Ding²  Jun Cui²  Jiannan Zhao³ 

[1] Key Laboratory of Lunar and Deep Space Exploration, National Astronomical Observatories, Chinese Academy of Sciences;Planetary Environmental and Astrobiological Research Laboratory, School of Atmospheric Sciences, Sun Yat-sen University;Planetary Science Institute, School of Earth Sciences, China University of Geosciences (Wuhan);

关键词: Moon;    Regolith;    Ground penetrating radar;    Loss tangent;    Chang’e-3;   

DOI  :  10.1186/s40645-020-00340-4

来源: DOAJ

【 摘 要 】

Abstract Using the high-frequency lunar penetrating radar data obtained by the Chang’e-3 mission, we apply the frequency-shift method to calculate the decay rate of the electromagnetic wave in the regolith-like ejecta deposits of the Ziwei crater. The radar data are divided into segments according to the navigation points along the traverse route of the Yutu rover. For each segment, we calculate the bulk loss tangent of materials within the top ~ 50 ns of the radar data based on the frequency decreasing rate of the electromagnetic wave. The loss tangent varies from ~ 0.011–0.017 along the route of Yutu, and it is within the range of the measured loss tangent of Apollo regolith samples. Using the empirical relationship between loss tangent and TiO2 + FeO content derived from the Apollo lunar samples, we estimate the TiO2 + FeO content for the bulk regolith along the route of Yutu, which is ~ 23–30 wt.%. This value is comparable with that estimated using both orbital reflectance spectral data and in situ observation made by the Yutu rover. The loss tangent derived along the route of Yutu is larger than the average value of returned lunar samples, which is mainly caused by the larger content of TiO2 + FeO at the landing site compared to the global average. Variations of the TiO2 + FeO content along the route of Yutu are mainly due to the excavation of the Ziwei crater. The TiO2 + FeO content map derived by the radar has a much higher spatial resolution compared to orbital observation, testifying the feasibility of this technique for regional geology study.

【 授权许可】

Unknown