Although its peak is still four years away, a new active period of Earth-threatening solar storms will be the weakest since 1928, predicts an international panel of experts led by NOAA’s Space Weather Prediction Center and funded by NASA.

Despite the prediction, Earth is still vulnerable to a severe solar storm. Solar storms are eruptions of energy and matter that escape from the sun and may head toward Earth, where even a weak storm can damage satellites and power grids, disrupting communications, the electric power supply and GPS. A single strong blast of “solar wind” can threaten national security, transport, financial services and other essential functions.