Published online by Cambridge University Press: 27 November 2018
We have analyzed the data on yearly mean international sunspot number (RZ) during the period 1610 – 2015 and orbital positions (ecliptic longitudes) of the giant planets in each 10-day interval during the period 1600 – 2099. We determined mean absolute difference ($\overline{\psi _D}$) of the orbital positions of the giant planets in each interval. We find that there exits a good correlation between cycle amplitude (RM, i.e. the maximum value of RZ) and the value of $\overline{\psi _D}$ at cycle maximum, suggesting that on longer time scales low/high solar activity associated with less/large spread in orbital positions of the giant planets (i.e. with a low/high value of $\overline{\psi _D}$).
Formerly with Indian Institute of Astrophysics, Bengaluru-560 034.