St. Elmo's fire is a plasma (i.e. a hot, ionized gas) that forms arounds the tips of raised, pointed conductors during thunderstorms. It is known as a corona discharge or point discharge to physicists. The few people that have had the privilege of viewing an actual St. Elmo's fire have given various descriptions. It has been seen with different physical characteristics depending on the conditions of the viewing. It could be blue to bluish-white, silent to emitting a hissing sound, and ghostly to solid. Some people belive that the Hindenburg was ignited by St. Elmo's fire in 1937, however this theory has yet to be proven.

St. Elmo's fire occurs during thunderstorms - generally after the most severe part of the storm has passed - when the air reaches a very high voltage. These conditions are necessary to accumulate a charge large enough to create the phenomenon. It is always found attached to a grounded conductor with a sharp point; the most common are masts of sailing ships, church steeples, airplane wings or propellers, or even horns of cattle. The non-attached version of St. Elmo's fire is known as Ball Lightning.

In research, we have found one case of a person claiming to have replicated St. Elmo's fire. A man used a homemade 50 kilovolt power power supply onto which he soldered a pin. As the power flowed, the tip of the pin began to give off a faint blue ionic discharge (glow) which he claimed to be St. Elmo's fire.