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Geomagnetic activity in December 1985
Mean Ap13.0No. 503 of 1138
G1+ days5
G3+ days0
Max Ap4630 Dec 1985
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Dec 1985 | 5- | 15 | G1 |
| 13 Dec 1985 | 5+ | 30 | G1 |
| 19 Dec 1985 | 6- | 41 | G2 |
| 28 Dec 1985 | 5+ | 35 | G1 |
| 30 Dec 1985 | 6o | 46 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| December 1984 | 17.8 | 13 | 0 |
| December 1985 | 13.0 | 5 | 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 13.0 in December 1985, No. 503 of 1138 months since 1932; 5 days reached G1 or higher.