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Geomagnetic activity in December 1990
Mean Ap7.0No. 1004 of 1138
G1+ days0
G3+ days0
Max Ap174 Dec 1990
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| – | – | – | – |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| December 1989 | 16.3 | 10 | 1 |
| December 1990 | 7.0 | 0 | 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 7.0 in December 1990, No. 1004 of 1138 months since 1932; 0 days reached G1 or higher.