Scientists have identified the Sun’s tachocline—a thin layer deep below the surface—as the source of powerful magnetic forces driving solar storms. The discovery could improve space weather forecasts and provide earlier warnings for disruptions to satellites and power systems.Scientists have identified the Sun’s tachocline—a thin layer deep below the surface—as the source of powerful magnetic forces driving solar storms. The discovery could improve space weather forecasts and provide earlier warnings for disruptions to satellites and power systems.