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Geomagnetic activity in September 1978
Mean Ap18.4No. 195 of 1138
G1+ days9
G3+ days1
Max Ap10929 Sep 1978
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Sep 1978 | 5o | 21 | G1 |
| 2 Sep 1978 | 5- | 20 | G1 |
| 8 Sep 1978 | 6- | 24 | G2 |
| 9 Sep 1978 | 5o | 31 | G1 |
| 25 Sep 1978 | 6- | 36 | G2 |
| 26 Sep 1978 | 6o | 36 | G2 |
| 27 Sep 1978 | 6+ | 51 | G2 |
| 28 Sep 1978 | 6+ | 50 | G2 |
| 29 Sep 1978 | 8o | 109 | G4 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 1977 | 15.9 | 8 | 2 |
| September 1978 | 18.4 | 9 | 1 |
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 18.4 in September 1978, No. 195 of 1138 months since 1932; 9 days reached G1 or higher.