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Geomagnetic activity in December 2009
Mean Ap1.9No. 1138 of 1138
G1+ days0
G3+ days0
Max Ap614 Dec 2009
Daily Ap
Daily max Kp
| Date | Max Kp | Ap | Level |
|---|---|---|---|
| – | – | – | – |
Same month a year earlier
| Month | Mean Ap | G1+ | G3+ |
|---|---|---|---|
| December 2008 | 4.5 | 0 | 0 |
| December 2009 | 1.9 | 0 | 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 1.9 in December 2009, No. 1138 of 1138 months since 1932; 0 days reached G1 or higher.