1. Institute for Space‐Earth Environmental ResearchNagoya University Nagoya Japan
2. Department of Earth and Planetary Science, Graduate School of ScienceUniversity of Tokyo Tokyo Japan
3. World Data Center for GeomagnetismKyoto University Kyoto Japan
4. New Jersey Institute of Technology Newark New Jersey USA
5. Applied Physics LaboratoryJohns Hopkins University Laurel Maryland USA
6. Aerospace Corporation El Segundo California USA
7. Institute for the Study of Earth, Oceans, and SpaceUniversity of New Hampshire Durham New Hampshire USA
8. Los Alamos National Laboratory Los Alamos New Mexico USA