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Geomagnetic activity in April 1975
Mean Ap15.7No. 313 of 1138
G1+ days12
G3+ days0
Max Ap529 Apr 1975
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 6 Apr 1975 | 5o | 15 | G1 |
| 7 Apr 1975 | 6- | 25 | G2 |
| 8 Apr 1975 | 6- | 32 | G2 |
| 9 Apr 1975 | 6o | 52 | G2 |
| 10 Apr 1975 | 5+ | 35 | G1 |
| 11 Apr 1975 | 5+ | 34 | G1 |
| 12 Apr 1975 | 6- | 27 | G2 |
| 13 Apr 1975 | 6- | 29 | G2 |
| 14 Apr 1975 | 5- | 21 | G1 |
| 20 Apr 1975 | 6- | 25 | G2 |
| 21 Apr 1975 | 6o | 23 | G2 |
| 23 Apr 1975 | 5- | 25 | G1 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 1974 | 21.3 | 19 | 0 |
| April 1975 | 15.7 | 12 | 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 15.7 in April 1975, No. 313 of 1138 months since 1932; 12 days reached G1 or higher.