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Geomagnetic activity in October 1940
Mean Ap14.2No. 404 of 1138
G1+ days7
G3+ days3
Max Ap617 Oct 1940
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Oct 1940 | 7o | 40 | G3 |
| 3 Oct 1940 | 5- | 19 | G1 |
| 7 Oct 1940 | 7o | 61 | G3 |
| 8 Oct 1940 | 7- | 49 | G3 |
| 22 Oct 1940 | 5- | 16 | G1 |
| 25 Oct 1940 | 5- | 13 | G1 |
| 26 Oct 1940 | 5+ | 28 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| October 1939 | 21.7 | 12 | 5 |
| October 1940 | 14.2 | 7 | 3 |
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.
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About this page
Mean Ap 14.2 in October 1940, No. 404 of 1138 months since 1932; 7 days reached G1 or higher.