ST. ELMO'S FIRE

'St. Elmo's Fire' is an electrical weather phenomenon in which visible plasma is created by a coronal discharge originating from a grounded object in an atmospheric electric field (such as those generated by thunderstorms).
St. Elmo's fire is named after St. Erasmus of Formiae (also called St. Elmo), the patron saint of sailors (who sometimes held its appearance to be auspicious). Alternatively, Peter Gonzalez is said to be the St. Elmo after whom St. Elmo's fire has its name.
Ball lightning is often erroneously identified as St. Elmo's Fire. They are separate and distinct meteorological phenomena^[1].

Contents

Observation

Scientific Explanation

Historical Observations

In Literature

In Popular Culture

References

See also

External links

Observation

Physically, 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. St. Elmo's Fire can also appear on leaves, grass, and even at the tips of cattle horns^[2]. Often accompanying the glow is a distinct hissing or buzzing sound.
In 1750, Benjamin Franklin hypothesized that a pointed iron rod during a lightning storm would light up at the tip, similar in appearance to St. Elmo's fire.^[3][4]

Scientific Explanation

Although referred to as "fire", St. Elmo's Fire is in fact 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. Approximately 1,000 - 30,000 volts per centimeter is required to induce St. Elmo's Fire; however, this number is greatly dependent on the geometry of the object in question. Sharp points tend to require lower voltage levels to produce the same result because electric fields are more concentrated in areas of high curvature, thus discharges are more intense at the end of pointed object^[5].
The nitrogen and oxygen in earth's atmosphere causes St. Elmo's Fire to fluoresce with blue or violet light; this is similar to the mechanism that causes neon lights to glow.

Historical Observations

In ancient Greece, the appearance of a single one was called Helena and two were called Castor and Pollux. 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 ''The Elements and Their Inhabitants'' [3].
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"^[6].
References to St. Elmo's fire, also known as "corposants" or "corpusants" from the Portuguese ''corpo santo''^[7] ("holy body"), can be found in the works of Julius Caesar (''De Bello Africo'', 47), Pliny the Elder (''Naturalis Historia'', book 2, par. 101) , Herman Melville, and Antonio Pigafetta's journal of his voyage with Ferdinand Magellan. St. Elmo's fire was a phenomenon described in ''The Lusiads''.
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."^[8]
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.^[9]
St Elmo's fire were also seen during the Plains Outbreak of May 1955 in Kansas and Oklahoma (US) ^[10].

In Literature

One of the earliest references of St. Elmo's fire made in fiction can be found in Ludovico Ariosto's epic poem ''Orlando furioso'' (c. 1532). It is located in the 19th canto 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 forestay, the masts and yards all being gone, and gave them hope of calmer airs."
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'ld divide,
::And burn in many places; on the topmast,
::The yards and bowsprit, would I flame distinctly,
::Then meet and join."
Later 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 (Vol III, Ch.IV):
::"'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.'"

And in Herman Melville's ''Moby Dick'' (1851), Ch. CXIX, "The Candles", during which the ship ''Pequod'' is struck head-on by a typhoon:
::"'Look Aloft!' cried Starbuck. 'The St. Elmo's Lights (corpus sancti) corporsants! the corporsants!'
::All the yardarms were tipped with a pallid fire, and touched at each tri-potential lightning rod with three tapering white flames, each of the three tall masts was silently burning in that sulphurous air, like three gigantic wax tapers before an altar...
::[Stubb] cried, "The corpusants have mercy on us all!"
::...in all my voyagings seldom have I heard a common oath when God's burning finger has been laid on the ship..."
There is also a possible reference^[11] to St. Elmo's fire in Samuel Taylor Coleridge's ''The Rime of the Ancient Mariner'' (1798):
::"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."

In Popular Culture

In the comic book Tintin in Tibet by Herge, Captain Haddock's ice axe is hit by St. Elmo's fire.
St Elmo's fire is also shown in the 1980's Japanese-French cartoon, "The Mysterious Cities of Gold".
In the 1980's version of Astroboy, St Elmo's Fire appears atop Viking ships in the episode "The World of Odin".
"St. Elmo's Fire" is a song by Brian Eno on his 1975 album Another Green World.
In the 1961 movie "The Last Sunset" St Elmo's fire is depicted. While perched above a herd of cattle they have been driving, Kirk Douglas points out the phenomenon to Dorothy Malone's character. Blue light is visible throughout the herd.
The 1985 movie "St. Elmo's Fire" while not a literal interpretation of the phenomenon is metaphorically related. The picture was nominated for Best Album of Original Score Written for a Motion Picture or Television Special in 1986. The title track by John Parr was a #1 hit. http://en.wikipedia.org/wiki/St._Elmo's_Fire_(Man_in_Motion)

References

1. Barry, J.D. (1980a) ''Ball Lightning and Bead Lightning: Extreme Forms of Atmospheric Electricity''. 8-9. New York and London: Plenum Press. ISBN 0-306-40272-6
2. Heidorn, K., Ph.D. ''Weather Elements: The Fire of St. Elmo''. Retrieved on July 2, 2007.
3. Van Doren, Carl. ''Benjamin Franklin'', The Viking Press, New York, 1938. p. 159. Quoted text from May 1750 letter published in "Gentleman's Magazine" at ''http://www.math.tamu.edu/~stecher/489/Ben/science.shtml''.[1]
4. Additional reference may be made from Yale University's ''The Papers of Benjamin Franklin'' collection at ''http://www.yale.edu/franklinpapers/index.html''.[2]
5. Scientific American. ''Ask The Experts: Physics''. Retrieved on July 2, 2007.
6. ''Folk-lore and folk-stories of Wales'', The Sea, Lakes, Rivers and Wells, Marie Trevelyan, 1909.
7. The American Heritage Dictionary
8. Darwin Correspondence Project, ''Letter 178 — Darwin, C. R. to Henslow, J. S., [23 July –] 15 Aug [1832]'' [4]
9. http://inamidst.com/lights/wisp/brand1777
10. Storm Electricity Aspects of the Blackwell/Udall Storm of 25 May 1955 - Don Burgess, University of Oklahoma (CIMMS)
11. Ower, John. ''The "Death-Fires", the "Fire-Flags" and the Corposant in "The Rime of the Ancient Mariner"''. Philological Quarterly, vol. 70 no. 2, p. 199-218. 1991

See also

★ Ball lightning

★ Naga fireballs

★ Will o' the wisp

External links

★ - Video of St. Elmo's Fire (around 2:00 in the left window)

★ http://www.islandnet.com/~see/weather/elements/stelmo.htm