How Cold? Researchers Predict Large Decrease in Sunspot Activity
NASA’s forecast for the next solar cycle (25) reveals it will be the weakest of the last 200 years.
The maximum of this next cycle — measured in terms of sunspot number, a standard measure of solar activity level — could be 30 to 50% lower than the most recent one.
The agency’s results show that the next cycle will start in 2020 and reach its maximum in 2025