Table 1. Locations, distances to the epicenter and traveling times of the ionosonde. The distance is computed by the spherical coordinate with the Earth’s radius of 6371 km.
Ionosonde | Distance (km) | dt1 (sec) | dt2 (sec) | dt3 (sec) |
|---|---|---|---|---|
WAK (45.2°N, 141.8°E) | 769 | N/A | 817 | 6217 |
KOK (35.7°N, 139.5°E) | 387 | N/A | 817 | N/A |
YAM (31.2°N, 130.6°E) | 1,334 | N/A | 2617 | 8017 |
OKI (26.7°N, 128.2°E) | 1,850 | 817 | 2617 | 9817 |
CHL (25.0°N, 121.2°E) | 2,482 | 1417 | 2917 | 11917 |