Japan Geoscience Union Meeting 2023

Presentation information

[J] Oral

P (Space and Planetary Sciences ) » P-CG Complex & General

[P-CG19] Planetary Magnetosphere, Ionosphere, and Atmosphere

Fri. May 26, 2023 9:00 AM - 10:15 AM Exhibition Hall Special Setting (2) (Exhibition Hall 8, Makuhari Messe)

convener:Hiroyuki Maezawa(Department of Physics, Osaka Metropolitan University), Naoki Terada(Graduate School of Science, Tohoku University), Kanako Seki(Graduate School of Science, University of Tokyo), Takeshi Imamura(Graduate School of Frontier Sciences, The University of Tokyo), Chairperson:Yuki Nakamura(Department of Geophysics, Graduate School of Science, Tohoku University), Hiroyuki Maezawa(Department of Physics, Osaka Metropolitan University), Naoki Terada(Graduate School of Science, Tohoku University)

9:00 AM - 9:15 AM

[PCG19-01] Dynamics of Low-Energy Ions and Electrons in Mercury's Magnetosphere: A Comparison Between Mio's First and Second Flybys

*Yuki Harada1, Yoshifumi Saito2, Sae Aizawa2,3, Nicolas André3, Lina Hadid4, Dominique Delcourt4, Moa Brita Persson3,5, Markus Fraenz6, Shoichiro Yokota7, Andréi Fedorov3, Wataru Miyake8, Emmanuel Penou3, Alain Barthe3, Jean-André Sauvaud3, Bruno Katra4, Wolfgang Baumjohann9, Ayako Matsuoka1, Werner Magnes10, Hans-Ulrich Auster11, Daniel Schmid10, David Fischer10, Manabu Shinohara12, Yoshimasa Tanaka13, Akiko Fujimoto14, Masaki Matsushima15, Yasuhito Narita10, Shoya Matsuda16, Go Murakami2 (1.Kyoto University, 2.ISAS, JAXA, 3.IRAP, CNRS-UPS-CNES, 4.LPP-CNRS-Sorbonne Université-Ecole Polytechnique, 5.University of Tokyo, 6.Max-Planck-Institute for Solar System Research, 7.Osaka University, 8.Tokai University, 9.Austrian Academy of Sciences, 10.The Space Research Institute, Austrian Academy of Sciences, 11.Institute of Geophysics and Extraterrestrial Physics, Technical University of Braunschweig, 12.National Institute of Technology, Kagoshima College, 13.National Institute of Polar Research, 14.Kyushu Institute of Technology, 15.Tokyo Institute of Technology, 16.Kanazawa University)

Keywords:Mercury, Mio, Magnetosphere

The first two Mercury flybys by Mio have revealed new aspects of the highly dynamic magnetosphere of Mercury. Near the magnetopause and bow shock, rapid fluctuations of particle fluxes were detected at unprecedentedly high-time resolutions. In the nightside magnetotail, we identify periodic variations in the ion and electron fluxes. In the inner part of the magnetosphere, Mio observed complicated energy-time structures such as energy dispersions and inverted V's. A comparison of the data from the two flybys indicates that Mercury's magnetosphere was in completely different states, presumably resulting from different solar wind conditions. The high-quality plasma data with a help of magnetic field measurements obtained by Mio enable us to investigate the boundary dynamics, low-frequency wave activity, and substorm-related processes to an extent not achieved by the previous missions. We report up-to-date results from the ongoing efforts of data analysis regarding Mio's first two Mercury flybys.