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Geomagnetic activity in September 1973
Mean Ap14.1No. 418 of 1138
G1+ days7
G3+ days2
Max Ap6323 Sep 1973
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 9 Sep 1973 | 8- | 44 | G4 |
| 10 Sep 1973 | 6o | 27 | G2 |
| 22 Sep 1973 | 5+ | 17 | G1 |
| 23 Sep 1973 | 7o | 63 | G3 |
| 24 Sep 1973 | 5- | 28 | G1 |
| 25 Sep 1973 | 6- | 27 | G2 |
| 26 Sep 1973 | 5+ | 25 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 1972 | 12.9 | 5 | 2 |
| September 1973 | 14.1 | 7 | 2 |
Dates and time slots are UTC. Kp is the 3-hourly planetary geomagnetic index (0–9); Ap is the daily average disturbance. G1–G5 follow the NOAA storm scale (Kp 5- and above counted as G1). Aurora visibility also depends on weather and location. The latest values are preliminary.
About this page
Mean Ap 14.1 in September 1973, No. 418 of 1138 months since 1932; 7 days reached G1 or higher.