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Geomagnetic activity in September 2005
Mean Ap20.2No. 146 of 1138
G1+ days8
G3+ days4
Max Ap10111 Sep 2005
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| 2 Sep 2005 | 7- | 39 | G3 |
| 3 Sep 2005 | 5+ | 27 | G1 |
| 4 Sep 2005 | 5- | 24 | G1 |
| 10 Sep 2005 | 6- | 33 | G2 |
| 11 Sep 2005 | 8- | 101 | G4 |
| 12 Sep 2005 | 7o | 75 | G3 |
| 13 Sep 2005 | 6o | 44 | G2 |
| 15 Sep 2005 | 7o | 52 | G3 |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| September 2004 | 8.6 | 5 | 0 |
| September 2005 | 20.2 | 8 | 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 20.2 in September 2005, No. 146 of 1138 months since 1932; 8 days reached G1 or higher.