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Geomagnetic activity in April 1985
Mean Ap21.1No. 127 of 1138
G1+ days12
G3+ days4
Max Ap10321 Apr 1985
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 1 Apr 1985 | 5+ | 23 | G1 |
| 3 Apr 1985 | 5- | 20 | G1 |
| 8 Apr 1985 | 5+ | 15 | G1 |
| 9 Apr 1985 | 6+ | 38 | G2 |
| 19 Apr 1985 | 5o | 21 | G1 |
| 20 Apr 1985 | 7- | 53 | G3 |
| 21 Apr 1985 | 8+ | 103 | G4 |
| 26 Apr 1985 | 5o | 30 | G1 |
| 27 Apr 1985 | 6- | 33 | G2 |
| 28 Apr 1985 | 7o | 61 | G3 |
| 29 Apr 1985 | 6o | 17 | G2 |
| 30 Apr 1985 | 7+ | 42 | G3 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 1984 | 25.3 | 15 | 3 |
| April 1985 | 21.1 | 12 | 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 21.1 in April 1985, No. 127 of 1138 months since 1932; 12 days reached G1 or higher.