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Geomagnetic activity in May 1947
Mean Ap14.0No. 428 of 1138
G1+ days8
G3+ days1
Max Ap5224 May 1947
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 13 May 1947 | 5- | 18 | G1 |
| 15 May 1947 | 5o | 29 | G1 |
| 16 May 1947 | 5o | 36 | G1 |
| 22 May 1947 | 5- | 9 | G1 |
| 23 May 1947 | 6- | 24 | G2 |
| 24 May 1947 | 8- | 52 | G4 |
| 28 May 1947 | 5o | 19 | G1 |
| 29 May 1947 | 5o | 22 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| May 1946 | 17.6 | 10 | 3 |
| May 1947 | 14.0 | 8 | 1 |
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 14.0 in May 1947, No. 428 of 1138 months since 1932; 8 days reached G1 or higher.