Distribution of flares on the Sun: Super active regions and active zones of 1980-1985

Coordinates of energetic solar flares observed with the Hard X-Ray Burst Spectrometer during the period were analyzed. Important discoveries resulting from this analysis are as follows: (1) A small number (28) of superactive regions produced the majority of the major flares during this period. These super active regions are large, complex active regions containing large sunspots. (2) There exist active zones, in which the flare occurrence rate is much higher. Two active zones are in the Northern Hemisphere, and two in the Southern Hemisphere. The longitudinal separation of the two active zones in the same hemisphere is about 180 degrees, but the active zones of the Southern Hemisphere are misaligned from those of the Northern Hemisphere by about 80 degrees. The rotation period of the active zones is 26.75 days. Active zones last several years or longer. (3) There is a hint of active center rotating at a period of 23.7 days. It is possible that active centers in deep layer rotate with such a period.