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Geomagnetic activity in December 1974
Mean Ap15.5No. 330 of 1138
G1+ days6
G3+ days0
Max Ap429 Dec 1974
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 9 Dec 1974 | 5+ | 42 | G1 |
| 13 Dec 1974 | 5- | 22 | G1 |
| 18 Dec 1974 | 5- | 28 | G1 |
| 19 Dec 1974 | 5- | 27 | G1 |
| 25 Dec 1974 | 5- | 12 | G1 |
| 27 Dec 1974 | 5- | 21 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| December 1973 | 11.4 | 5 | 0 |
| December 1974 | 15.5 | 6 | 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 15.5 in December 1974, No. 330 of 1138 months since 1932; 6 days reached G1 or higher.