What causes the naval phenomenon called St. Elmos Fire?
St. Elmo’s fire is an electroluminescent coronal discharge caused by the ionization of the air during thunderstorms inside of a strong electric field. Although referred to as “fire”, St. Elmo’s fire is in fact a low density, relatively low temperature plasma caused by massive atmospheric electrical potential differences which exceed the dielectric breakdown value of air at around 3 megavolts per meter.
