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Geomagnetic activity in September 1947
Mean Ap32.2No. 18 of 1138
G1+ days16
G3+ days4
Max Ap10025 Sep 1947
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 3 Sep 1947 | 7+ | 84 | G3 |
| 4 Sep 1947 | 5o | 35 | G1 |
| 6 Sep 1947 | 5- | 22 | G1 |
| 7 Sep 1947 | 7- | 45 | G3 |
| 8 Sep 1947 | 5o | 18 | G1 |
| 11 Sep 1947 | 5o | 17 | G1 |
| 13 Sep 1947 | 6- | 48 | G2 |
| 14 Sep 1947 | 6+ | 59 | G2 |
| 15 Sep 1947 | 6+ | 62 | G2 |
| 16 Sep 1947 | 5o | 21 | G1 |
| 17 Sep 1947 | 6o | 55 | G2 |
| 18 Sep 1947 | 5+ | 43 | G1 |
| 22 Sep 1947 | 5o | 33 | G1 |
| 23 Sep 1947 | 6+ | 42 | G2 |
| 24 Sep 1947 | 7+ | 90 | G3 |
| 25 Sep 1947 | 8- | 100 | G4 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 1946 | 34.3 | 13 | 7 |
| September 1947 | 32.2 | 16 | 4 |
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 32.2 in September 1947, No. 18 of 1138 months since 1932; 16 days reached G1 or higher.