Intense Magnetopause Erosion at Earth During the May 2024 Solar Storm
Abstract Earth's main magnetic field forms the magnetosphere, shielding the planet from solar wind plasma. Southward interplanetary magnetic fields erode the magnetosphere, a process known as magnetopause erosion, allowing solar wind penetration close to the Earth. While magnetic reconnection is considered a key driver, the mechanism during super geomagnetic storms remains unclear due to limited in situ observations. Here, we report a magnetopause crossing by Arase at 4.96 R E during the May 2024 superstorm, one of the innermost magnetopause crossings ever detected by magnetospheric spacecraft. We observe an anomalous and global reduction in magnetic field intensity extending from the inner magnetosphere to the magnetopause, suggesting global weakening by magnetospheric currents. This weakened magnetic field is responsible for the enhanced magnetopause erosion.
Authors
- Kunihiro Keika (ORCID: https://orcid.org/0000-0003-0265-4318)
- B N Wang
- Iku Shinohara (ORCID: https://orcid.org/0000-0003-2700-0353)
- Naritoshi Kitamura (ORCID: https://orcid.org/0000-0002-2397-273X)
- Ayako Matsuoka (ORCID: https://orcid.org/0000-0001-5777-9711)
- Atsuki Shinbori (ORCID: https://orcid.org/0000-0002-6018-7431)
- Shoichiro Yokota (ORCID: https://orcid.org/0000-0001-8851-9146)
- Kazushi Asamura (ORCID: https://orcid.org/0000-0002-6076-3814)
- Tomoaki Hori (ORCID: https://orcid.org/0000-0001-8451-6941)
- Y. Kazama (ORCID: https://orcid.org/0000-0002-9070-8269)
- Rumi Nakamura (ORCID: https://orcid.org/0000-0002-2620-9211)
- Satoshi Kasahara (ORCID: https://orcid.org/0000-0002-3479-772X)
- Chae‐Woo Jun (ORCID: https://orcid.org/0000-0003-2914-2910)
- Yoshizumi Miyoshi (ORCID: https://orcid.org/0000-0001-7998-1240)
- Sunny Wing-Yee Tam
- Tzu-Fang Chang (ORCID: https://orcid.org/0000-0001-8014-2719)
- Kazuhiro Yamamoto (ORCID: https://orcid.org/0000-0002-2515-8643)
- Shiang-Yu Wang (ORCID: https://orcid.org/0000-0001-6491-1901)
- Mariko Teramoto (ORCID: https://orcid.org/0000-0001-5983-1149)
Institutions
- Institute of Astronomy and Astrophysics, Academia Sinica (TW)
- Austrian Academy of Sciences (AT)
- Kyushu Institute of Technology (JP)
- Japan Aerospace Exploration Agency (JP)
- Kyung Hee University (KR)
- Space Research Institute (AT)
- Institute of Space and Astronautical Science (JP)
- Data Analysis Center for Geomagnetism and Space Magnetism, Graduate School of Science, Kyoto University (JP)
- Institute for Space-Earth Environmental Research, Nagoya University (JP)
- The University of Tokyo (JP)
- Academia Sinica (TW)
- National Cheng Kung University (TW)
- The University of Osaka (JP)
Publication Details
- Journal
- Geophysical Research Letters
- Published
- 2026-11-04
- DOI
- https://doi.org/10.1029/2026gl125027
- Primary Topic
- Ionosphere and magnetosphere dynamics
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Academia Sinica
- Ministry of Science and Technology, Taiwan
- National Cheng Kung University
- Japan Society for the Promotion of Science