Carrington's Solar Flare

The night of September 1, 1859 was one of the most extraordinary of modern times. On this night a great aurora, probably the greatest during the past two hundred years, spread down from the polar regions to cloak two thirds of the entire earth's sky. Even the residents of Cuba saw aurora directly overhead that night.

This spectacular happening followed some hours after another historic event, the first recorded sighting of a solar flare by the unaided human eye. Though recorded separately by two persons located some miles apart, the flare become known as Carrington's Solar Flare after one of the two, English astronomer Richard Carrington.

Carrington spotted the flare when it erupted from a group of sunspots he had been observing on a projected image of the sun. Carrington was quite taken aback by his sighting and could not at first quite believe what he was seeing, since no one had reported such a thing before. Later he recognized that the huge aurora to follow may have been related to the remarkable solar flare but was too cautious to make such a bold claim. However it soon become obvious to others that there was a connection and that this in fact was the discovery that bright solar flares do initiate great auroral displays.

The extent to which that great red aurora of September 1, 1859, covered the earth was not fully documented until a hundred years later. In 1960, Donald S. Kimball of the Geophysical Institute published a report showing maps where the aurora was seen. To accomplish the task, he utilized a large collection of data accumulated by a well-known scientist, Elias Loomis of Yale University. Reports from astronomical observatories formed part of the collection, but it also included many newspaper reports, personal letters and reports from ships at sea.