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Geomagnetic activity in September 1985
Mean Ap12.8No. 525 of 1138
G1+ days7
G3+ days0
Max Ap3519 Sep 1985
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 14 Sep 1985 | 6+ | 29 | G2 |
| 15 Sep 1985 | 6o | 18 | G2 |
| 16 Sep 1985 | 5+ | 33 | G1 |
| 19 Sep 1985 | 6o | 35 | G2 |
| 20 Sep 1985 | 5o | 29 | G1 |
| 26 Sep 1985 | 5o | 19 | G1 |
| 27 Sep 1985 | 5- | 17 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 1984 | 23.6 | 10 | 3 |
| September 1985 | 12.8 | 7 | 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 12.8 in September 1985, No. 525 of 1138 months since 1932; 7 days reached G1 or higher.