Table 1 Periodicities and harmonics of the Aa time series associated with the Moon and the Sun
From: New perspectives on contributing factors to the monthly behavior of the aa geomagnetic index
Cycle | Maxima (days) | Related to | Minima (days) | Related to |
|---|---|---|---|---|
11 | 14.49 | M—1st harmonic | 6.84 6.95 | S—2nd harmonic S—2nd harmonic |
12 | – | 13.61 | S—1st harmonic | |
13 | 27.51 13.83 13.60 | S S—1st harmonic S—1st harmonic | 29.02 27.38 | M S |
14 | 30.18 26.72 | M S | 29.02 27.38 | M S |
15 | 13.45 | S—1st harmonic | 26.74 27.48 | S S |
16 | 13.61 | S—1st harmonic | 29.06 13.46 | M S—1st harmonic |
17 | 13.90 27.37 | S—1st harmonic S | – | |
18 | 27.27 14.08 29.16 | S S—1st harmonic M | 26.43 29.65 | S M |
19 | 13.60 | S—1st harmonic | 31.42 6.94 | M S |
20 | 13.63 29.89 28.87 | S—1st harmonic M M | 31.29 14.72 | M M |
21 | – | 13.85 15.77 | S M—1st harmonic | |
22 | – | 26.97 15.11 | S M—1st harmonic | |
23 | 13.42 27.46 | S—1st harmonic S | 13.49 27.37 | S—1st harmonic S |
24 | 13.39 28.82 | S—1st harmonic M |