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arXiv · 2411.13719

Persistent but weak magnetic field at Moon's midlife revealed by Chang'e-5 basalt

Shuhui Cai·Huafeng Qin·Huapei Wang·Chenglong Deng·Saihong Yang·Ya Xu·Chi Zhang·Xu Tang·Lixin Gu·Xiaoguang Li·Zhongshan Shen·Min Zhang·Kuang He·Kaixian Qi·Yunchang Fan·Liang Dong·Yifei Hou·Pingyuan Shi·Shuangchi Liu·Fei Su·Yi Chen·Qiuli Li·Jinhua Li·Ross N. Mitchell·Huaiyu He·Chunlai Li·Yongxin Pan·Rixiang Zhu
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Abstract

The evolution of the lunar magnetic field can reveal the Moon's interior structure, thermal history, and surface environment. The mid-to-late stage evolution of the lunar magnetic field is poorly constrained, and thus the existence of a long-lived lunar dynamo remains controversial. The Chang'e-5 mission returned the heretofore youngest mare basalts from Oceanus Procellarum uniquely positioned at mid-latitude. We recovered weak paleointensities of 2-4 uT from the Chang'e-5 basalt clasts at 2 billion years ago, attestting to the longevity of a lunar dynamo until at least the Moon's midlife. This paleomagnetic result implies the existence of thermal convection in the lunar deep interior at the lunar mid-stage which may have supplied mantle heat flux for the young volcanism.

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Shuhui Cai, Huafeng Qin, Huapei Wang, Chenglong Deng, Saihong Yang, Ya Xu, Chi Zhang, Xu Tang, Lixin Gu, Xiaoguang Li, Zhongshan Shen, Min Zhang, Kuang He, Kaixian Qi, Yunchang Fan, Liang Dong, Yifei Hou, Pingyuan Shi, Shuangchi Liu, Fei Su, Yi Chen, Qiuli Li, Jinhua Li, Ross N. Mitchell, Huaiyu He, Chunlai Li, Yongxin Pan, Rixiang Zhu. 2024-11-20. Persistent but weak magnetic field at Moon's midlife revealed by Chang'e-5 basalt. https://doi.org/10.1126/sciadv.adp3333

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