Journal article
Magnetic Reconnection as a Potential Trigger for Magnetotail Flapping at Mars: Insights From MAVEN and Tianwen‐1 Observations
AGU advances, Vol.7(2), e2026AV002343
04/2026
DOI: 10.1029/2026AV002343
Appears in UI Libraries Support Open Access
Abstract
Magnetotail current sheet (CS) flapping is a universal plasma phenomenon observed at multiple planets, yet its triggering mechanisms remain poorly understood outside of Earth. At Mars, single‐spacecraft observations have also reported tail flapping, but the processes responsible for its onset have never been identified. In this study, we investigate the potential correlation between magnetic reconnection and magnetotail flapping using multipoint measurements from Mars Atmosphere and Volatile EvolutioN (MAVEN) and Tianwen‐1 (TW‐1) missions. We analyze an example event in which MAVEN observed a reconnection‐associated CS crossing in the near tail while TW‐1 simultaneously detected CS flapping further downtail. A statistical survey of joint observations from November 2021 to February 2024 identifies that about two‐thirds of TW‐1 flapping events coincide with reconnection signatures observed by MAVEN. Multiple magnetic flux ropes were also detected before or during flapping intervals, similar to previous observations at Earth, suggesting that reconnection‐generated magnetic flux ropes may propagate tailward and drive plasma instabilities that trigger the tail flapping at Mars. These results provide the first multipoint evidence of a potential statistical correlation between magnetic reconnection and magnetotail flapping at Mars, enabling us to explore the potential triggering mechanism of magnetotail flapping. Our findings also offer new insights into Martian magnetotail dynamics and broaden the comparative understanding of this fundamental plasma process across planetary environments. The solar wind, a continuous stream of charged particles from the Sun, interacts with planetary magnetic fields and atmospheres to form long magnetic tails behind planets. Within these tails, thin layers of electric current—called current sheets—sometimes move or “flap,” affecting how magnetic energy and plasma are transported. At Earth, observations from multiple spacecraft have shown that magnetic reconnection, a process in which magnetic field lines break and reconnect to release stored magnetic energy, can drive such motions. At Mars, however, the causes of current sheet flapping at the magnetotail have remained uncertain because previous studies only relied on a single spacecraft measurement. In this study, we use simultaneous observations from NASA's MAVEN spacecraft and China's Tianwen‐1 orbiter to explore what triggers flapping in Mars's magnetotail. The results suggest that magnetic reconnection may also play a key role in triggering these motions at Mars, providing the first multipoint evidence of this connection and advancing our understanding of the plasma dynamics within the magnetotail of Mars. Multipoint observations from MAVEN and Tianwen‐1 reveal a potential link between magnetic reconnection and the magnetotail flapping at Mars Magnetotail current sheet (CS) flapping at Mars may be triggered by plasma instabilities driven by reconnection‐generated magnetic flux ropes First multipoint investigation of the magnetotail CS flapping mechanism beyond Earth
Details
- Title: Subtitle
- Magnetic Reconnection as a Potential Trigger for Magnetotail Flapping at Mars: Insights From MAVEN and Tianwen‐1 Observations
- Creators
- Yuanzheng Wen - University of IowaJasper S. Halekas - University of IowaHan‐Wen Shen - University of Iowa, Physics and AstronomyChi Zhang - Boston UniversityRobert J. Lillis - University of California, BerkeleyJiawei Gao - Boston UniversityNorberto Romanelli - Goddard Space Flight CenterLong Cheng - Swedish Institute of Space PhysicsChuanfei Dong - Boston UniversityYingjuan Ma - University of California, Los AngelesYaxue Dong - University of Colorado BoulderShaosui Xu - University of California, BerkeleyDavid A. Brain - University of Colorado BoulderJunfeng Qin - University of California, BerkeleyJared R. Espley - Goddard Space Flight CenterDavid L. Mitchell - University of California, BerkeleyChristian Mazelle - Institute for Resource Analysis and PolicyJames P. McFadden - University of California, BerkeleyShannon M. Curry - University of Colorado Boulder
- Resource Type
- Journal article
- Publication Details
- AGU advances, Vol.7(2), e2026AV002343
- DOI
- 10.1029/2026AV002343
- ISSN
- 2576-604X
- eISSN
- 2576-604X
- Publisher
- Wiley
- Grant note
- French space agency CNES National Aeronautics and Space Administration: NNH10CC04C, 80GSFC24M0006
Y. Wen acknowledges Prof. Zhaojin Rong, Dr. Takuya Hara, Prof. Ivan Vasko, Dr. Andrei Runov, Dr. Weijie Sun, Dr. Jacob R. Gruesbeck, Murti Nauth, and Kyle Webster for helpful discussions on this study. We acknowledge NASA and the MAVEN mission for support through grant NNH10CC04C to the University of Colorado and by subcontract to Space Sciences Laboratory, University of California, Berkeley. N. Romanelli is supported by NASA under award number 80GSFC24M0006. We also acknowledge the Tianwen-1 MOMAG team for providing public data access and support. Part of this work is supported by the French space agency CNES for the observations obtained with the SWEA instrument.
- Language
- English
- Date published
- 04/2026
- Academic Unit
- Physics and Astronomy
- Record Identifier
- 9985153387902771
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