St. Elmo's fire

For other uses, see St. Elmo's Fire (disambiguation).

St. Elmo's fire on a ship at sea

St. Elmo's fire (also St. Elmo's light) is a weather phenomenon in which luminous plasma is created by a coronal discharge from a sharp or pointed object in a strong electric field in the atmosphere (such as those generated by thunderstorms or created by a volcanic eruption).

St. Elmo's fire is named after St. Erasmus of Formia (also called St. Elmo, one of the two Italian names for St. Erasmus, the other being St. Erasmo), the patron saint of sailors. The phenomenon sometimes appeared on ships at sea during thunderstorms and was regarded by sailors with religious awe for its glowing ball of light, accounting for the name. Sailors may have considered St. Elmo's fire as a good omen (as a sign of the presence of their patron saint).

Characteristics

St. Elmo's fire is a bright blue or violet glow, appearing like fire in some circumstances, from tall, sharply pointed structures such as lightning rods, masts, spires and chimneys, and on aircraft wings or nose cones. St. Elmo's fire can also appear on leaves and grass, and even at the tips of cattle horns. Often accompanying the glow is a distinct hissing or buzzing sound. It is sometimes confused with ball lightning.

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.

Cause

St. Elmo's fire is a form of plasma. The electric field around the object in question 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 approximately 100 kV/m is required to induce a discharge in 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 preferably 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 fluoresce with blue or violet light; this is similar to the mechanism that causes neon lights to glow.

In History and Culture

• In ancient Greece, the appearance of a single one was called Helene (Greek: Ἑλένη), literally meaning torch, and two were called Kastor and Polydeuces (names of the mythological twin brothers of Helen). Occasionally, it was associated with the Greek element of fire, as well as with one of Paracelsus's elementals, specifically the salamander, or, alternatively, with a similar creature referred to as an acthnici.
• Welsh mariners knew it as canwyll yr ysbryd ("spirit-candles") or canwyll yr ysbryd glân ("candles of the Holy Ghost"), or the "candles of St. David".
• Many Russian sailors have seen them throughout the years. To them, they are "Saint Nicholas" or "Saint Peter's lights". They were 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 reportedly was 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 being seen around the fleet's ships multiple times off the coast of South America. The sailors saw these as favorable omens.
• On 26 August 1883, the British warship Charles Ball sailing the Sunda Strait en route to Hong Kong came within 20 km of the exploding Krakatau volcano and witnessed a great deal of static electricity in the atmosphere, generated by the movement of tiny particles of rocks and droplets of water from the volcano's steam, which caused spectacular brush discharges taking place from the masts and rigging of the ship.
• St Elmo's fire was also seen during the 1955 Great Plains tornado outbreak in Kansas and Oklahoma (US).
• Among the phenomena experienced on British Airways Flight 9 on 24 June 1982 were glowing light flashes along the leading edges of the aircraft, which were seen by both passengers and crew. While it 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.
• The ill-fated Air France Flight 447 flight from Rio de Janeiro–Galeão (GIG) 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 on the disaster.

Notable observations

Julius Caesar

References to St. Elmo's fire can be found in the works of Julius Caesar (De Bello Africo, 47), Pliny the Elder (Naturalis Historia, book 2, par. 101), Alcaeus frag. 34, and Antonio Pigafetta's journal of his voyage with Ferdinand Magellan. St. Elmo's fire, also known as "corposants" or "corpusants" from the Portuguese corpo santo ("holy body"), was a phenomenon described in The Lusiads.

Zheng He

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

The power of the goddess, having indeed been manifested in previous times, has been abundantly revealed in the present generation. In the midst of the rushing waters it happened that, when there was a hurricane, suddenly a divine lantern was seen shining at the masthead, and as soon as that miraculous light appeared the danger was appeased, so that even in the peril of capsizing one felt reassured and that there was no cause for fear.

— Admiral Zheng He and his associates (Changle inscription)

Robert Burton

Robert Burton wrote of St. Elmo's fire in his Anatomy of Melancholy: "Radzivilius, the Lithunian 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".

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 Hillsborough, 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 23d, 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. 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: "There, directly over where we had been standing, upon the main top-gallant mast-head, was a ball of light, which the sailors name a corposant (corpus sancti), and which the mate had called out to us to look at. They were all watching it carefully, for sailors have a notion, that if the corposant rises in the rigging, it is a sign of fair weather, but if it comes lower down, there will be a storm".

Nikola Tesla

Nikola Tesla created St. Elmo's Fire in 1899 while testing out a Tesla coil at his laboratory in Colorado Springs, USA. 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. (Added by K.G.H. Nicholes: My father is History Professor Mark M. Heald's son, physicist Mark A. Heald. They did indeed witness the Hindenburg tragedy, but my grandfather had no prior experience of St. Elmo's Fire, and no background to support his identification of what he saw as such. My father has protested people's uncritical passing along of his father's assumption on many occasions.)

William L. Laurence

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

I noticed a strange eerie light coming through the window high above in the Navigator's cabin and as I peered through the dark all around us I saw a startling phenomenon. The whirling giant propellers had somehow become great luminous discs of blue flame. The same luminous blue flame appeared on the plexiglass windows in the nose of the ship, and on the tips of the giant wings it looked as though we were riding the whirlwind through space on a chariot of blue fire. It was, I surmised, a surcharge of static electricity that had accumulated on the tips of the propellers and on the dielectric material in the plastic windows. One's thoughts dwelt anxiously on the precious cargo in the invisible ship ahead of us. Was there any likelihood of danger that this heavy electric tension in the atmosphere all about us may set it off? I express my fears to Captain Bock, who seems nonchalant and imperturbed at the controls. He quickly reassures me: "It is a familiar phenomenon seen often on ships. I have seen it many times on bombing missions. It is known as St. Elmo's Fire."

In literature

One of the earliest references to the phenomenon appears in Alcaeus's Fragment 34a about the Dioscuri, or Castor and Pollux. It is also referenced in Homeric Hymn 33 to the Dioscuri who were from Homeric times associated with it. Whether the Homeric Hymn antedates the Alcaeus fragment is unknown.

St. Elmo's Fire is also mentioned in the novel, Castaways of the Flying Dutchman by Brian Jacques.

The phenomenon appears to be described first in the Gesta Herwardi, written around 1100 and concerning an event of the 1070s. However, one of the earliest direct references to St. Elmo's fire made in fiction can be found in Ludovico Ariosto's epic poem Orlando Furioso (1516). It is located in the 17th canto (19th in the revised edition of 1532) after a storm has punished the ship of Marfisa, Astolfo, Aquilant, Grifon, and others, for three straight days, and is positively associated with hope:

But now St. Elmo's fire appeared, which they had so longed for, it settled at the bows of a fore stay, the masts and yards all being gone, and gave them hope of calmer airs.

— Ludovico Ariosto, 1516

In Shakespeare's The Tempest (c. 1623), Act I, Scene II, St. Elmo's fire acquires a more negative association, appearing as evidence of the tempest inflicted by Ariel according to the command of Prospero:

PROSPERO

Hast thou, spirit,

Perform'd to point the tempest that I bade thee?

ARIEL

To every article.

I boarded the king's ship; now on the beak,

Now in the waist, the deck, in every cabin,

I flamed amazement: sometime I'd divide,

And burn in many places; on the topmast,

The yards and bowsprit, would I flame distinctly,

Then meet and join.

— Act I, Scene II, The Tempest

The fires are also mentioned as "death fires" in Samuel Taylor Coleridge's The Rime of the Ancient Mariner.

About, about, in reel and rout, The death fires danced at night; The water, like a witch's oils, Burnt green and blue and white.

Later in 18th century and 19th century literature associated St. Elmo's fire with bad omen or divine judgment, coinciding with the growing conventions of Romanticism and the Gothic novel. For example, in Ann Radcliffe's The Mysteries of Udolpho (1794), during a thunderstorm above the ramparts of the castle:

"And what is that tapering of light you bear?" said Emily, "see how it darts upwards,—and now it vanishes!"

"This light, lady", said the soldier, "has appeared to-night as you see it, on the point of my lance, ever since I have been on watch; but what it means I cannot tell".

"This is very strange!" said Emily.

"My fellow-guard", continued the man, "has the same flame on his arms; he says he has sometimes seen it before...he says it is an omen, lady, and bodes no good".

"And what harm can it bode?" rejoined Emily.

"He knows not so much as that, lady".

— Vol. III, Ch. IV, The Mysteries of Udolpho

In Herman Melville's novel Moby-Dick, Starbuck points out "corpusants" during a thunder storm in the Japanese sea in chapter 119 "The Candles".

St. Elmo's fire makes an appearance in The Adventures of Tintin comic, Tintin in Tibet, by Hergé. Tintin recognizes the phenomenon on Captain Haddock's ice-axe.

In Kurt Vonnegut's Slaughterhouse-Five, Billy Pilgrim sees the phenomenon on soldiers' helmets and on rooftops. Vonnegut's The Sirens of Titan also notes the phenomenon affecting Winston Niles Rumfoord's dog, Kazak, the Hound of Space, in conjunction with solar disturbances of the chrono-synclastic infundibulum.

In "On The Banks of Plum Creek" by Laura Ingalls Wilder St. Elmo's fire is seen by the girls and Ma during one of the blizzards. It was described as coming down the stove pipe and rolling across the floor following Ma's knitting needles; it didn't burn the floor (pages 309-310). The phenomenon as described, however, is more similar to ball lightning.

In television

On the children's television series The Mysterious Cities of Gold (1982), Episode 4 shows St. Elmo's Fire affecting the ship as it sailed past the Strait of Magellan. The real-life footage at the end of the episode has snippets of an interview with Japanese sailor Fukunari Imada, whose comments were translated to "Although I've never seen St. Elmo's Fire, I'd certainly like to. It was often considered a bad omen as it played havoc with compasses and equipment". The TV series also referred to St. Elmo's Fire as being a bad omen during the cartoon. The footage was captured as part of his winning solo yacht race in 1981.

On the American television series Rawhide, in a 1959 episode titled "Incident of the Blue Fire", cattle drovers on a stormy night see St. Elmo's Fire glowing on the horns of their steers, which the men regard as a deadly omen. St. Elmo's Fire is also referenced in a 1965 episode of Bonanza in which religious pilgrims staying on the Cartwright property believe an experience with St. Elmo's Fire is the work of Satan.

In movies

St. Elmo's fire is featured in the movie Moby Dick (1956), when Captain Ahab is stopped by it from killing Starbuck.

In the movie The Last Sunset (1961), Outlaw/Cowhand Brendan 'Bren' O'Malley (Kirk Douglas) rides in from the herd and leads the recently widowed, and his former flame, Belle Breckenridge (Dorothy Malone) to an overview of the cattle. As he takes the rifle from her he proclaims, "Something out there, you could live five lifetimes, and never see again," the audience is then shown a shot of the cattle with a blue or violet glow coming from their horns. "Look. St. Elmo's Fire. Never seen it except on ships," O'Malley says as Belle says, "I've never seen it anywhere. What is it?" Trying to win her back he says, "Well a star fell and smashed and scattered its glow all over the place."

In Lars von Trier's 2011 film Melancholia, the phenomenon is clearly observed in the opening sequence and later in the film as the rogue planet Melancholia approaches Earth for an impact event.

In music

Brian Eno's third studio album Another Green World (1975) contains a song titled "St. Elmo's Fire" in which guesting King Crimson guitarist Robert Fripp (credited with playing "Wimshurst guitar" in the liner notes) improvises a lightning-fast solo that would imitate an electrical charge between two poles on a Wimshurst high voltage generator.

Michael Frank's song "St Elmo's Fire" was released on his album "The Art of Tea" in 1976. His song has since been sampled various times by artists like Absolutely Fabolous, & more.

The first song in Susumu Hirasawa's album Aurora, "Stone Garden" (石の庭 Ishi no Niwa), contains a line which translates to

That day when I melted away into the sky
Burning like St. Elmo's sacred fire

"St. Elmo's Fire (Man in Motion)" is a song recorded by John Parr. It hit number one on the Billboard Hot 100 on September 7, 1985, remaining there for two weeks. It was the main theme for Joel Schumacher's 1985 film St. Elmo's Fire.

See also

• Ball lightning
• British Airways Flight 9
• Earthquake light
• Foo fighter, WWII UFO observations
• Hessdalen Lights
• List of plasma (physics) articles
• Naga fireballs, rising from Mekong river
• Sprite (lightning)
• St. Elmo's Fire (film)
• Triboelectric effect
• Will-o'-the-wisp

External links

• St. Elmo's fire photographed on the flight deck of an airliner
• Video of St. Elmo's fire observed from the cockpit of an airliner on YouTube
• St. Elmo's Fire on Lake Monona on YouTube