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arXiv · 2303.07078

Interplanetary Coronal Mass Ejections and Stream Interaction Regions observed by Tianwen-1 and Maven at Mars

Yutian Chi·Chenglong Shen·Long Cheng·Bingkun Yu·Bin Miao·Yuming Wang·Tielong Zhang·Zhuxuan Zou·Mengjiao Xu·Zonghao Pan·Zhenpeng Su·Jingnan Guo·Dongwei Mao·Zhihui Zhong·Zhiyong Zhang·Junyan Liu·Can Wang·Zhiyong Wu·Guoqiang Wang·Sudong Xiao·Kai Liu·Xinjun Hao·Yiren Li·Manming Chen·Yang Du
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Abstract

Tianwen-1 spacecraft (Wan et al. 2020) is China's first Mars exploration mission. The Mars Orbiter Magnetometer (MOMAG) is a scientific instrument aboard the Tianwen-1 mission that is designed to study magnetic fields at Mars, including the solar wind to the magnetosheath and the ionosphere. Using the first Tianwen-1/MOMAG data that is publicly available, we present interplanetary coronal mass ejection (ICME) and stream interaction region (SIR) catalogues based on in-situ observations at Mars between November 16, 2021, and December 31, 2021. We compared the magnetic field intensity and vector magnetic field measurements from Tianwen-1/MOMAG and Mars Atmospheric Volatile EvolutioN (MAVEN)/MAG during the ICME and SIR interval and found a generally good consistency between them. Due to MAVEN's orbital adjustment since 2019, the Tianwen-1/MOMAG instrument is currently the almost unique interplanetary magnetic field monitor at Mars. The observations indicate that the MOMAG instrument on Tianwen-1 is performing well and can provide accurate measurements of the vector magnetic field in the near-Mars solar wind space. The multi-point observations combining MOMAG, MINPA, and MEPA on board Tianwen-1 with MAG, SWIA, and STATIC on board MAVEN will open a window to systematically study the characteristic of ICMEs and SIRs at Mars, and their influences on the Martian atmosphere and ionosphere.

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Yutian Chi, Chenglong Shen, Long Cheng, Bingkun Yu, Bin Miao, Yuming Wang, Tielong Zhang, Zhuxuan Zou, Mengjiao Xu, Zonghao Pan, Zhenpeng Su, Jingnan Guo, Dongwei Mao, Zhihui Zhong, Zhiyong Zhang, Junyan Liu, Can Wang, Zhiyong Wu, Guoqiang Wang, Sudong Xiao, Kai Liu, Xinjun Hao, Yiren Li, Manming Chen, Yang Du. 2023-03-13. Interplanetary Coronal Mass Ejections and Stream Interaction Regions observed by Tianwen-1 and Maven at Mars. https://doi.org/10.3847/1538-4365/acd191

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