The surge of extra current can blow out transformers, overload power systems and leave millions of people in the dark. The last solar maximum occurred in 1989. The solar flare sent a cloud of highly charged particles careening toward earth at hypersonic speed. But the Hydro-Quebec power grid was hit hardest by the storm. The system was completely knocked out, leaving millions of Canadians in the dark, some for months.
Solar storms can also have more disastrous consequences.
During the 1989 solar maximum, a powerful gas line exploded and destroyed part of the Trans-Siberian Railroad. Two passenger trains burst into flames, killing 500 people. The Russians initially suspected sabotage, but many believe massive electrical currents from solar storms could have flowed through the pipeline and corroded the metal, leading to the explosion. Severe, magnetic solar storms can occur anytime, but they tend to happen more often during solar maximum, just as thunderstorms tend to happen more frequently during the summer. In May of last year, as the cycle began to approach solar maximum, experts believe a magnetic storm knocked out the Galaxy 4 satellite over the United States.