But predicting the strength and timing of these cycles has been difficult because scientists can’t see the magnetic fields deep inside the sun, where the activity originates. For decades, solar physicists have used computer simulations called dynamo models to understand how the sun generates its magnetic field. The duo, instead of relying on theoretical shapes, fed their 3D computer model real observations of the sun’s surface field. So by monitoring the surface magnetic fields today, scientists can get a reliable warning of how active the sun will be later. “Our findings on one hand strengthen our physics understanding of the generation of solar magnetic fields and on the other … predict when the sun will be active, violent, and very dangerous for space-borne technological assets and communications,” Dr. Hazra told The Hindu.