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Geomagnetic activity in April 1977
Mean Ap15.6No. 319 of 1138
G1+ days7
G3+ days2
Max Ap496 Apr 1977
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 4 Apr 1977 | 5+ | 24 | G1 |
| 6 Apr 1977 | 7o | 49 | G3 |
| 7 Apr 1977 | 7- | 48 | G3 |
| 8 Apr 1977 | 5- | 27 | G1 |
| 19 Apr 1977 | 6+ | 48 | G2 |
| 20 Apr 1977 | 5o | 28 | G1 |
| 25 Apr 1977 | 6- | 22 | G2 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| April 1976 | 17.4 | 9 | 1 |
| April 1977 | 15.6 | 7 | 2 |
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 15.6 in April 1977, No. 319 of 1138 months since 1932; 7 days reached G1 or higher.