Something amazing happened in the first few days of September, 1859. Telegraph long-lines in Europe and the United States crashed frequently and some telegraph operators were electrically zapped, knocked into unconsciousness. Motors and other electrical devices burst into flame. There were unusually bright and wild auroral light shows in the night skies. Anything that could measure a magnetic field, or be affected by magnetic disturbances, ranging from sailor's compasses to sensitive magnetometers, behaved erratically.

What caused this trauma? The answer came from an amateur astronomer who had been observing the Sun from his private observatory. Richard Carrington, son of a wealthy brewer, had been following the development of a huge sunspot group many times the size of the Earth, and speculated that the terrestrial effects were related to small transient brightenings he observed near the sunspots.

Since Carrington's observation, links between storms and flares on the Sun have become indelibly linked to magnetic disturbances on Earth and in the Earth's upper atmosphere. As our civilization adopted forms of electricity to create the modern world of commerce, transportation and communication it is essential that we have as complete a knowledge of sun-earth linkages as possible.  We still do not know precisely what to expect, especially for storms of the scale observed by Carrington.