Active longitudes in the period of overlap of 11-year cycles

Abstract

It is shown that “active longitudes” for the sunspots of old and new cycles manifest themselves approximately in the same longitudinal intervals and remain for several 11-year cycles. To be more accurate, they vanish in some cycles but then appear again at the same longitudinal intervals in the other cycles. The entire period is characterized by a total of four active longitudes. The old-cycle sunspots observed at low equatorial latitudes in the Northern and Southern Hemispheres are characterized by a shift by ≈180°, which indicates antipodality of the active longitudes in the Northern and Southern Hemispheres. In the case of highlatitude sunspots (new-cycle sunspots), the best correlation is observed for the shift of ≈90°. There is supposedly a dependence of the rotation speed of active longitudes on the secular cycle.