St. Elmo's Fire

St. Elmo's Fire is a glow produced by charged objects inside of a strong electric field, such as cattle horns during a thunderstorm, or sharp objects in the middle of a tornado. Benjamin Franklin correctly observed in 1749 that it is electric in nature. Physically, it is a bright bluish-white glow, appearing like fire in some circumstances.

In ancient Greece, the appearance of a single one was called Helena and two were called Pollux and Castor. It is named after Erasmus of Formiae, the patron of sailors, because it would appear most often on metal objects of a ship at sea.

For a possibly related phenomenon, see Ball lightning

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St. Elmo's Fire was the defining movie of the 1980s brat pack which consisted of Ally Sheedy, Rob Lowe, Demi Moore, Molly Ringwald, Judd Hirsch and Emilio Estevez.