The Sun usually exhibits ~11 year cycles of activity, but the historical sunspot record shows quite a large variance on this average figure. Here at the Talkshop, we have been developing a theory which relates solar activity levels to the motion of the planets, and in particular the motion of Jupiter, Earth and Venus. Simple indexes of ‘most aligned days’ were devised by Jean-Pierre Desmoulins, and later by NASA physicist Ching Cheh Hung, which was replicated by Talkshop contributor Roy Martin.
Taking Roy’s index as a starting point, later in 2010 I re-weighted variables (reducing Venus) and factored in solar wind speed and planetary alignment along the Parker spiral, which produced this black curve:
Ignore the solar cycle 24 prediction Roy made from 2010 (red curve) and notice the severe drop in the planetary index (black curve) around the middle of this decade, followed by a resurgence by 2019. It’s going to be interesting to see if solar cycle 24 ‘reawakens’ towards the end of this decade. I predict the current lull in activity won’t behave like a normal ~11 year solar minimum. Instead we’ll see activity picking up again within months.