When will the next sunspot cycle start?
Cycle 20 started in October 1964. Cycle 21 started in June 1976, and the previous cycle, Number 22, started in September 1986. Sunspot maximum for Cycle 22 occurred in July 1989 and since the last few cycles have had durations of 11.67 and 10.25 years, sunspot minimum and the end of this cycle will probably occur sometime in 1996-1997. In fact, the current Cycle 23 began in October 1996. After Cycle 23, cycle 24 will probably begin around 2007.
Copyright 1997 Dr. Sten Odenwald
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