Overwhelming abundance of Earth-origin high-energy heavy ions is crucial key to the development of super geomagnetic storms—Arase satellite observation of the May 2024 super geomagnetic storm—

2026-06-29

An international research led by Dr. Naritoshi Kitamura (Designated Assistant Professor, Center for Integrated Data Science) has demonstrated that the vast majority of high-energy ions contributing to the ring current during the May 2024 super geomagnetic storm were heavy ions of terrestrial origin, and has successfully identified the temporal variations and spatial distributions of these ions. This is based on an analysis of observational data obtained by the ARASE satellite in near-Earth space, combined with simultaneous observations of the solar wind. Although the energy driving geomagnetic storms originates from the solar wind, the supply of ions from the Earth’s ionosphere is overwhelmingly important in replenishing the ring current and plays a crucial role in the development of super geomagnetic storms. Although such events are rare, from a space weather perspective, it is important to understand and predict changes in the space environment during super geomagnetic storms. These observational results provide valuable insights into the physical processes underlying the development of super geomagnetic storms.

Journal: Science Advances
Title: Extreme dominance of Earth-origin heavy ions in the intense ring current near the Earth during the May 2024 super geomagnetic storm
Authors: Naritoshi Kitamura, Kazuhiro Yamamoto, Shoichiro Yokota, Satoshi Kasahara, Ayako Matsuoka, Kazushi Asamura, Yusuke Ebihara, Lynn M. Kistler, Kunihiro Keika, Atsuki Shinbori, Tomoaki Hori, Yoshizumi Miyoshi, Akimasa Ieda, Chae-Woo Jun, Mariko Teramoto, Masahito Nosé, Masafumi Hirahara, Kanako Seki, Nana Higashio, and Iku Shinohara
https://doi.org/10.1126/sciadv.aee1069

Nagoya University Press Release
https://en.nagoya-u.ac.jp/news/articles/earths-ionosphere-supplied-vast-majority-of-ring-current-ions-during-may-2024-super-geomagnetic-storm-study-finds/