Bracing for a solar superstorm.

The article discusses solar superstorms, rare bursts of intense solar activity which hit the earth with a blast of solar particles. One recorded in 1859 created intense aurora light effects as far south as the Caribbean, and wreaked havoc with magnetic compasses and electric telegraph systems. The importance of guarding satellites and the power grid against major damage from such an event is emphasized. INSETS: Impact of a Coronal Mass Ejection;The 1859 Superstorm;IT'S RAINING PROTONS.