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Geomagnetic activity in September 1975
Mean Ap9.7No. 783 of 1138
G1+ days3
G3+ days0
Max Ap2610 Sep 1975
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 9 Sep 1975 | 5o | 24 | G1 |
| 10 Sep 1975 | 5+ | 26 | G1 |
| 12 Sep 1975 | 5- | 19 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 1974 | 23.2 | 15 | 2 |
| September 1975 | 9.7 | 3 | 0 |
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 9.7 in September 1975, No. 783 of 1138 months since 1932; 3 days reached G1 or higher.