Table 3 Number of sunspot area more than 3700 MSH for 100-year periods in the DHO and MA20 catalogues
From: Extremely large flares/multiple large flares expected from sunspot groups with large area
Data period | Number of sunspot area of more than 3700 MSH in the DHO catalogue | Number of sunspot area of more than 3700 MSH in the MA20 catalogue |
|---|---|---|
1879−1978 | 41 | 41 |
1889−1988 | 41 | 41 |
189 −1998 | 46 | 46 |
1909−2008 | 46 | 46 |
Average | 44 \(\pm\) 2.9 | 44 \(\pm\) 2.9 |