Skip to content
Surf Wiki
Save to docs
technology/web

From Surf Wiki (app.surf) — the open knowledge base

St. Elmo's fire

Luminous plasma created in an electric field

St. Elmo's fire

Summary

Luminous plasma created in an electric field

Illustration of St. Elmo's fire on a ship at sea
A350]] while going through a [[cumulonimbus cloud

St. Elmo's fire (also called corposant, Hermes fire, furole, witchfire or witch's fire) is a weather phenomenon in which luminous plasma is created by a corona discharge from a rod-like object such as a mast, spire, chimney, or animal horn in an atmospheric electric field. It has also been observed on the leading edges of aircraft and by US Air Force pilots.{{cite web | access-date = 9 September 2023

The intensity of the effect, a blue or violet glow around the object, often accompanied by a hissing or buzzing sound, is proportional to the strength of the electric field and therefore noticeable primarily during thunderstorms or volcanic eruptions.

St. Elmo's fire is named after St. Erasmus of Formia (also known as St. Elmo), the patron saint of sailors. The phenomenon, which can warn of an imminent lightning strike, was regarded by sailors with awe and sometimes considered to be a good omen.

Cause

St. Elmo's fire is a reproducible and demonstrable form of plasma. The electric field around the affected object causes ionization of the air molecules, producing a faint glow easily visible in low-light conditions. Conditions that can generate St. Elmo's fire are present during thunderstorms, when high-voltage differentials are present between clouds and the ground underneath. A local electric field of about 100 kV/m is required to begin an electric discharge in moist air. The magnitude of the electric field depends greatly on the geometry (shape and size) of the object. Sharp points lower the necessary voltage because electric fields are more concentrated in areas of high curvature, so discharges preferentially occur and are more intense at the ends of pointed objects.

The nitrogen and oxygen in the Earth's atmosphere cause St. Elmo's fire to emit blue or violet light via the same kind of mechanism that causes clear neon gas-discharge lamps to glow (without phosphors), albeit with a different colour due to the different gases involved.

In 1751, Benjamin Franklin hypothesized that a pointed iron rod would light up at the tip during a lightning storm, similar in appearance to St. Elmo's fire.

In an August 2020 paper, researchers in MIT's Department of Aeronautics and Astronautics demonstrated that St. Elmo's fire behaves differently in airborne objects versus grounded structures. They show that electrically isolated structures accumulate charge more effectively in high wind, in contrast to the corona discharge observed in grounded structures.

Research

Vacuum ultraviolet light

Researchers at Rutgers University have devised a method to generate vacuum ultraviolet light using different forms of lighting, by employing sharp conductive needles placed within a dense gas, such as xenon, contained in a cell. They achieve this by applying a high negative voltage to the needles in the xenon-filled cell, resulting in the efficient production of vacuum ultraviolet light. St. Elmo's Fire being similar, they believe it could be used as lighting but with a higher power source, thus increasing efficiency by over 50%.

In history and culture

  • In ancient Greece, the appearance of a single instance of St. Elmo's fire was called grc (), literally meaning "torch", with two instances referred to as Castor and Pollux, names of the mythological twin brothers of Helen.
  • After the medieval period, St. Elmo's fire was sometimes associated with the Greek element of fire, such as with one of Paracelsus's elementals, specifically the salamander, or, alternatively, with a similar creature referred to as an acthnici.
  • Welsh mariners referred to St. Elmo's fire as canwyll yr ysbryd or canwyll yr ysbryd glân ("candles of the Holy Ghost" or the "candles of St. David").
  • Russian sailors also historically documented instances of St. Elmo's fire, known as "Saint Nicholas" or "Saint Peter's lights", also sometimes called St. Helen's or St. Hermes' fire, perhaps through linguistic confusion.
  • St. Elmo's fire is reported to have been seen during the Siege of Constantinople by the Ottoman Empire in 1453. It was reportedly seen emitting from the top of the Hippodrome. The Byzantines attributed it to a sign that the Christian God would soon come and destroy the conquering Muslim army. According to George Sphrantzes, it disappeared just days before Constantinople fell, ending the Byzantine Empire.
  • Accounts of Magellan's first circumnavigation of the globe refer to St. Elmo's fire (calling it the body of St. Anselm) being seen around the fleet's ships multiple times off the coast of South America. The sailors saw these as favourable omens.
  • En route to Nagasaki with the Fat Man atom bomb on 9 August 1945, the B-29 Bockscar experienced an uncanny luminous blue plasma forming around the spinning propellers, "as though we were riding the whirlwind through space on a chariot of blue fire."
  • St Elmo's fire was seen during the 1955 Great Plains tornado outbreak in Kansas and Oklahoma.
  • Among the phenomena experienced on British Airways Flight 9 on 24 June 1982, were glowing light flashes along the leading edges of the aircraft, including the wings and cockpit windscreen, which were seen by both passengers and crew. While the bright flashes of light shared similarities with St Elmo's fire, the glow experienced was from the impact of ash particles on the leading edges of the aircraft, similar to that seen by operators of sandblasting equipment.
  • St. Elmo's fire was observed and its optical spectrum recorded during a University of Alaska research flight over the Amazon in 1995 to study sprites.
  • Ill-fated Air France Flight 447 from Rio de Janeiro–Galeão International Airport to Paris Charles de Gaulle Airport in 2009 is understood to have experienced St. Elmo's fire 23 minutes prior to crashing into the Atlantic Ocean; however, the phenomenon was not a factor in the disaster.
  • Apoy ni San Elmo – commonly shortened to santelmo – is a bad omen or a flying spirit in Filipino folklore, although the description for santelmo is more similar to ball lightning than St. Elmo's fire. There are various indigenous names for santelmo which has existed before the term santelmo was coined. The term santelmo originated from Spanish colonial rule in the Philippines.

Notable observations

Classical texts

St. Elmo's fire is referenced in the works of Julius Caesar (De Bello Africo, 47) and Pliny the Elder (Naturalis Historia, book 2, par. 101), Alcaeus frag. 34. Earlier, Xenophanes of Colophon had alluded to the phenomenon.

Zheng He

In 15th-century Ming China, Admiral Zheng He and his associates composed the Liujiagang and Changle inscriptions, the two epitaphs of the Ming treasure voyages, where they made a reference to St. Elmo's fire as a divine omen of Tianfei, the goddess of sailors and seafarers.

Accounts associated with Magellan and da Gama

Mention of St. Elmo's fire can be found in Antonio Pigafetta's journal of his 1519 to 1522 voyage with Ferdinand Magellan. St. Elmo's fire, also known as "corposants" or "corpusants" from the Portuguese corpo santo ("holy body"), is also described in The Lusiads (1572), the epic account of the voyages of discovery of Vasco da Gama (1469-1524).

Robert Burton

Robert Burton wrote of St. Elmo's fire in his Anatomy of Melancholy (1621): "Radzivilius, the Lithuanian duke, calls this apparition Sancti Germani sidus; and saith moreover that he saw the same after in a storm, as he was sailing, 1582, from Alexandria to Rhodes". This refers to the voyage made by Mikołaj Krzysztof "the Orphan" Radziwiłł in 1582–1584.

John Davis

On 9 May 1605, while on the second voyage of John Davis commanded by Sir Edward Michelborne to the East Indies, an unknown writer aboard the Tiger describes the phenomenon: "In the extremity of our storm appeared to us in the night, upon our maine Top-mast head, a flame about the bigness of a great Candle, which the Portugals call Corpo Sancto, holding it a most divine token that when it appeareth the worst is past. As, thanked be God, we had better weather after it".

Pierre Testu-Brissy

Pierre Testu-Brissy was a pioneering French balloonist. On 18 June 1786, he flew for 11 hours and made the first electrical observations as he ascended into thunderclouds. He stated that he drew remarkable discharges from the clouds by means of an iron rod carried in the basket. He also experienced Saint Elmo's fire.

William Bligh

William Bligh recorded in his log on Sunday 4 May 1788, on board HMS Bounty of 'Mutiny On The Bounty' fame: 'Corpo-Sant. Some electrical Vapour seen about the Iron at the Yard Arms about the Size of the blaze of a Candle.' The location of this event was in the South Atlantic sailing from Cape Horn, (having failed to round the cape in the winter months), en route to Cape of Good Hope and west of Tristan da Cunha. The log records the ship's location as: Latd. 42°:34'S, Longd (by the time keeper K2) as 34°:38'W. Reference: Log of the Proceedings of His Majestys Ship Bounty in a Voyage to the South Seas, (to take the Breadfruit plant from the Society Islands to the West Indies,) under the Command of Lieutenant William Bligh, 1 December 1787 – 22 October 1788 Safe 1/46, Mitchell Library, State Library of NSW

William Noah

William Noah, a silversmith convicted in London of stealing 2,000 pounds of lead, while en route to Sydney, New South Wales on the convict transport ship , recorded two such observations in his detailed daily journal. The first was in the Southern Ocean midway between Cape Town and Sydney and the second was in the Tasman Sea, a day out of Port Jackson: 26 June 1799: At 4 Began to Blow very Hard with Heavy Shower of Rain & Hail and Extraordinary Heavy Clap of Thunder & Lightning when fell a Cormesant [corposant] a Body of Fire which collect from the Lightning & Lodge itself in the Foretopmast Head where it was first seen by our Captain when followed a Heavy Clap of Thunder & Lightning which occasioned it to fall & Burst on the Main Deck the Electrific of the Bursting of this Ball of Fire had such power as to shake several of their Leg not only On the Main Deck as the fire Hung much round the smith Forge being Iron but had the same Effect on the Gun Deck & Orlop [deck] on several of the Convicts. 25 July 1799: We were now sourounded with Heavy Thunder & Lightning and the Dismal Element foaming all round us Shocking to see with a Cormesant Hanging at the Maintop mast Head the Seamen was here Shock'd when a flash of Lightning came Burst the Cormesant & Struck two of the Seamen for several Hours Stone Blind & several much hurt in their Eyes.

While the exact nature of these weather phenomena cannot be certain, they appear to be mostly about two observations of St. Elmo's fire with perhaps some ball lightning and even a direct lightning strike to the ship thrown into the mix.

James Braid

On 20 February 1817, during a severe electrical storm, James Braid, surgeon at Lord Hopetoun's mines at Leadhills, Lanarkshire, had an extraordinary experience whilst on horseback: On Thursday 20th, I was gratified for a few minutes with the luminous appearance described above [viz., "such flashes of lightning from the west, repeated every two or three minutes, sometimes at shorter intervals, as appeared to illumine the whole heavens"]. It was about nine o'clock, P.M. I had no sooner got on horseback than I observed the tips of both the horse's ears to be quite luminous: the edges of my hat had the same appearance. I was soon deprived of these luminaries by a shower of moist snow which immediately began to fall. The horse's ears soon became wet and lost their luminous appearance; but the edges of my hat, being longer of getting wet, continued to give the luminous appearance somewhat longer.

I could observe an immense number of minute sparks darting towards the horse's ears and the margin of my hat, which produced a very beautiful appearance, and I was sorry to be so soon deprived of it.

The atmosphere in this neighbourhood appeared to be very highly electrified for eight or ten days about this time. Thunder was heard occasionally from 15th to 23rd, during which time the weather was very unsteady: frequent showers of hail, snow, rain, &c.

I can find no person in this quarter who remembers to have ever seen the luminous appearance mentioned above, before this season, – or such a quantity of lightning darting across the heavens, – nor who have heard so much thunder at that season of the year.

This country being all stocked with sheep, and the herds having frequent occasion to pay attention to the state of the weather, it is not to be thought that such an appearance can have been at all frequent, and none of them to have observed it.|James Braid, 1817

Weeks earlier, reportedly on 17 January 1817, a luminous snowstorm occurred in Vermont and New Hampshire. Saint Elmo's fire appeared as static discharges on roof peaks, fence posts, and the hats and fingers of people. Thunderstorms prevailed over central New England.

Charles Darwin

Charles Darwin noted the effect while aboard the Beagle. He wrote of the episode in a letter to J. S. Henslow that one night when the Beagle was anchored in the estuary of the Río de la Plata: Everything is in flames – the sky with lightning, the water with luminous particles, and even the very masts are pointed with a blue flame. |Charles Darwin, 1832

Richard Henry Dana

In Two Years Before the Mast, Richard Henry Dana Jr., (1815–1882) describes seeing a corposant in the horse latitudes of the northern Atlantic Ocean. However, he may have been talking about ball lightning; as mentioned earlier, it is often erroneously identified as St. Elmo's fire:

The observation by R. H. Dana of this phenomenon in Two Years Before the Mast is a straightforward description of an extraordinary experience apparently only known to mariners and airline pilots.

Nikola Tesla

Nikola Tesla created St. Elmo's fire in 1899 while testing a Tesla coil at his laboratory in Colorado Springs, Colorado, United States. St. Elmo's fire was seen around the coil and was said to have lit up the wings of butterflies with blue halos as they flew around.

Mark Heald

A minute before the crash of the Luftschiffbau Zeppelin's LZ 129 Hindenburg on 6 May 1937, Professor Mark Heald (1892–1971) of Princeton saw St. Elmo's Fire flickering along the airship's back. Standing outside the main gate to the Naval Air Station, he watched, together with his wife and son, as the airship approached the mast and dropped her bow lines. A minute thereafter, by Heald's estimation, he first noticed a dim "blue flame" flickering along the backbone girder about one-quarter the length abaft the bow to the tail. There was time for him to remark to his wife, "Oh, heavens, the thing is afire," for her to reply, "Where?" and for him to answer, "Up along the top ridge" – before there was a big burst of flaming hydrogen from a point he estimated to be about one-third the ship's length from the stern.

William L. Laurence

St. Elmo's fire was reported by The New York Times reporter William L. Laurence on 9 August 1945, as he was aboard a plane following Bockscar on the way to Nagasaki.

Notes

References

References

  1. Jeffreys, M.D.W. (Jun., 1949), [https://www.jstor.org/stable/1256716 "Witch's Fire"], in ''[[Folklore (journal). Folklore]]''; Vol. 60, No. 2, pp. 286–290 (5 pages); Pub: Taylor & Francis, Ltd.
  2. Heidorn, Keith C.. (30 May 1998). "Weather Phenomenon and Elements: The Fire Of St. Elmo".
  3. (December 2014). "Wilderness Medical Society practice guidelines for the prevention and treatment of lightning injuries: 2014 update". Wilderness & Environmental Medicine.
  4. Eyers, Jonathan. (November 2023). "Don't Shoot the Albatross!: Nautical Myths and Superstitions". A&C Black.
  5. Bergreen, Laurence. (April 2021). "Over the Edge of the World: Magellan's Terrifying Circumnavigation of the Globe". Morrow.
  6. (2025). "Quantifying and mitigating electrical and environmental impacts of corona discharge". Scientific Reports.
  7. Van Doren, Carl. (1938). "Benjamin Franklin". The Viking Press.
  8. "The Papers of Benjamin Franklin".
  9. "How airplanes counteract St. Elmo's Fire during thunderstorms".
  10. (27 August 2020). "Corona Discharge in Wind for Electrically Isolated Electrodes". Journal of Geophysical Research: Atmospheres.
  11. Wallace, John. (November 2003). "Laboratory St. Elmo's fire produces VUV light". Laser Focus World.
  12. Lyd. Ost. 5
  13. (Poll. 10.191)
  14. (16 May 2008). "The Elements and Their Inhabitants".
  15. Trevelyan, Marie. (1909). "Folk-lore and folk-stories of Wales".
  16. "Will With A Wisp: John Brand (1777)".
  17. Pigafetta, Antonio. (25 October 2012). "Magellan's Voyage: A Narrative Account of the First Circumnavigation". Courier Corporation.
  18. Toll, I.W. (2020). Twilight of the Gods. War in the Western Pacific, 1944-1945. W.W. Norton & Company, Inc., New York.
  19. "Storm Electricity Aspects of the Blackwell/Udall Storm of May 25, 1955 – Don Burgess, University of Oklahoma (CIMMS)".
  20. Wescott et al. (1996) "The optical spectrum of aircraft St. Elmo's fire", Geophys. Res. Lett., 23(25), pp. 3687–90.
  21. (20 August 2008). "Peru95 - sprite observations over the upper Amazon".
  22. (1 June 2020). "What Really Happened Aboard Air France 447".
  23. [http://www.bea.aero/docspa/2009/f-cp090601.en/pdf/f-cp090601.en.pdf "Final Report On the accident on 1st June 2009 to the Airbus A330-203 registered F-GZCP operated by Air France flight AF 447 Rio de Janeiro – Paris."] {{Webarchive. link. (12 November 2020 Bureau d'Enquêtes et d'Analyses. N.p., July 2012. 12 March 2014)
  24. "The Enigmatic Philippine Origins of Trese's Santelmo".
  25. (2011). "A Presocratics Reader: Selected Fragments and Testimonia". Hackett.
  26. Dreyer, Edward L.. (2007). "Zheng He: China and the Oceans in the Early Ming Dynasty, 1405–1433". Pearson Longman.
  27. Needham, Joseph. (1959). "Science and Civilisation in China, Volume 3". Cambridge University Press.
  28. [http://www.thefreedictionary.com/p/corposants "Corposants"] {{Webarchive. link. (26 June 2021 ''The American Heritage Dictionary'')
  29. Markham, Albert. (1880). "Voyages and Works of John Davis". The Hakluyt Society.
  30. "William Noah 'A Voyage to Sydney in New South Wales in 1798 & 1799' and 'A Few Remarks of the County of Cumberland in New South Wales, 1798-1799".
  31. Braid, J.. (1817). "Account of a Thunder Storm in the Neighbourhood of Leadhills, Lanarkshire".
  32. "San Francisco, CA Weather Facts". Myforecast.com.
  33. [http://www.darwinproject.ac.uk/darwinletters/calendar/entry-178.html Darwin Correspondence Project, ''Letter 178 – Darwin, C. R. to Henslow, J. S., July 23 – August 15 1832''] {{webarchive. link. (3 September 2007)
  34. Dana, Richard Henry Jr., (1840) ''[[Two Years Before the Mast]]''. Chapter 33.
  35. (1993). "The Fantastic Inventions of Nikola Tesla". Adventures Unlimited.
  36. Robinson, Douglas. ''LZ-129 Hindenburg''. New York: Arco, 1964.{{page needed. (April 2021)
  37. Laurence, William L.. (9 September 1945). "Eyewitness Account of Atomic Bomb Over Nagasaki".
  38. "Alcaeus". [[Wesleyan University]].
  39. "Homeric Hymns 5–33". Theoi Greek Mythology.
  40. "Gesta Herwardi, Chapter XXIX".
  41. "The Ballad of Nat Turner".
  42. (25 April 2017). "Middle Passage".
  43. "Japanese wins solo yacht race across Pacific.".
  44. [http://www.tv.com/shows/rawhide/incident-of-the-blue-fire-135393/ "Incident of the Blue Fire"] {{Webarchive. link. (13 January 2020 , ''Rawhide'' (S02E11), originally aired 11 December 1959. TV.com. Retrieved 23 April 2017.)
  45. link. (26 June 2021 , ''Bonanza'' (S07E06), originally aired 17 October 1965. Entire episode is available for viewing on YouTube. Retrieved 23 April 2017.)
  46. [https://www.imdb.com/title/tt0529544/ "Devil on Her Shoulder"] {{Webarchive. link. (24 April 2017 , Internet Movie Database ([[IMDb]]). Retrieved 23 April 2017.)
Wikipedia Source

This article was imported from Wikipedia and is available under the Creative Commons Attribution-ShareAlike 4.0 License. Content has been adapted to SurfDoc format. Original contributors can be found on the article history page.

Want to explore this topic further?

Ask Mako anything about St. Elmo's fire — get instant answers, deeper analysis, and related topics.

Research with Mako

Free with your Surf account

Content sourced from Wikipedia, available under CC BY-SA 4.0.

This content may have been generated or modified by AI. CloudSurf Software LLC is not responsible for the accuracy, completeness, or reliability of AI-generated content. Always verify important information from primary sources.

Report