In 1859, one of the largest solar storms on record struck earth. Known as the Carrington Event, the storm damaged telegraph systems in Europe and North America.

Sparks leaped from telegraph machines, shocking operators and setting papers ablaze. A Pittsburgh telegraph manager reported electricity flowing through the wires was so powerful that platinum contacts were about to melt and “streams of fire” poured forth from the circuits. Telegraph pylons threw out sparks. People in Cuba and Honolulu saw northern lights and those in Chile saw southern lights. A solar storm of this magnitude today would cause widespread electrical disruptions, blackouts and extended outages of the electrical grid. Solar plasma also would threaten satellite communications.