[P-EM12] Coupling Processes in the Atmosphere-Ionosphere System

[PEM12-21] Investigation of the daytime sporadic-E layer by the RIDE campaign 2025

*Akinori Saito¹, Takumi Abe², Ayako Matsuoka³, Keigo Ishisaka⁴, Yoshifumi Saito², MASAHITO TAGAWA⁵, Atsushi Kumamoto⁶, Hirotsugu Kojima⁷, Satoshi Kurita⁷, KUMIKO YOKOTA⁵, Michi Nishioka⁸, Satoshi Andoh⁸, Susumu Saito⁹, Toru Takahashi⁹, Keisuke Hosokawa¹⁰, Hiroyuki Nakata¹¹, Tatsuhiro Yokoyama⁷, Huixin Liu¹², Takanori Nishiyama¹³, Mitsumu K. Ejiri¹³, Takatoshi Sakazaki¹ (1.Department of Geophysics, Graduate School of Science, Kyoto University, 2.Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3.Data Analysis Center for Geomagnetism and Space Magnetism, Graduate School of Science, Kyoto University, 4.Toyama Prefectural University, 5.Kobe University, 6.Department of Geophysics, Graduate School of Science, Tohoku University, 7.Research institute for sustainable humanosphere, Kyoto University, 8.National Institute of Information and Communications Technology, 9.Electronic Navigation Research Institute, National Institute of Maritime, Port, and Aviation Technology, 10.Department of Communication Engineering and Informatics, University of Electro-Communications, 11.Graduate School of Engineering, Chiba University, 12.Earth and Planetary Science Division, Kyushu University, 13.National Institute of Polar Research)

Keywords:Ionosphere, sporadic E layer, Radio wave propagation, sounding rocket

The Rocket Investigation of the Daytime E-region (RIDE) campaign is scheduled to take place in the summer of 2025 in Japan. This is a coordinated observational campaign involving the S-310-46 sounding rocket launched from Uchinoura, Japan, along with a ground-based network that includes ionosondes, VHF receivers, and GNSS receivers. The campaign was postponed due to technical issues with the sounding rocket in the summer of 2024." There are three objectives of this campaign as follows:
(1) Elucidate phenomena in which the interaction between neutral atmosphere and plasma is important by combining in-situ observations by the sounding rocket with a numerical model and ground-based observations.
(2) Develop instrumental packages to measure the neutral atmosphere, plasma, and electromagnetic fields for sounding rockets and satellites.
(3) Foster human resources for future missions.
This campaign is designed to reveal sporadic-E layers' formation and transportation process. Such information is essential for predicting anomalous radio wave propagation caused by sporadic-E layers. The ground-based network of ionosondes and GNSS receivers monitors the horizontal structure and movement of Es layers. This information will be used to make the launch decision for the sounding rocket aimed at the moderate or intense Es layer. Seven scientific payloads are carried on the RIDE rocket. These include the Neutral Mass Spectrometer (NMS), Neutral Density and Wind Instrument (IOG), Ion Velocity Analyzer (IVA), Impedance Probe (NEI), Fast Langmuir Probe (FLP), Electric Field Detector (EFD), and Magnetometer (MAG). The physical parameters of both the neutral and ionized atmosphere, inside and outside the Es layers, will provide crucial information to help solve several unresolved questions about the Es layers. Why are Es layers so sporadic? Do they have frontal structures? What role does the electric field play in their formation and transport? Do atmospheric gravity waves contribute significantly? Combination of high-resolution data of the in-situ measurement, and wide field-of-view data of the ground-based network, and three-dimensional numerical simulation coupled with a global model is expected to elucidate the Es layer processes that have been unclear so far. The outline of the observation and scientific targets will be presented in the presentation.