Scientists predict that activity in the next solar cycle will be the weakest in the last 200 years. The number of sunspots in the Sun's next 11-year cycle, starting in 2020, could be 30% to 50% lower than in its current cycle.
Sunspots are regions on the Sun with magnetic fields thousands of times stronger than Earth's. Fewer of them at the point of maximum solar activity means fewer dangerous blasts of radiation spewing into space.
The research is led by Irina Kitiashvili, a scientist at the Bay Area Environmental Research Institute at NASA's Ames Research Center.
Kitiashvili's method differs from other prediction tools in the raw material for its forecast. Previously, researchers used the number of sunspots to estimate the activity of the solar magnetic field. The new approach takes advantage of direct observations of magnetic fields on the surface of the Sun -- data which have existed only for the last four solar cycles.
Combining information from observations of the Sun's surface with estimates of its interior activity generated a forecast designed to be more reliable than that from any one source alone.
Knowing how the Sun will behave lets us protect technology we depend on: satellite missions studying the universe from space; landers and rovers heading to the Moon and Mars; and the telecommunications satellites right in our own backyards.