Ball lightning

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For other uses, see Ball lightning (disambiguation).

Ball lightning reportedly takes the form of a glowing, floating object often the size and shape of a basketball, but it can also be golf ball sized or smaller. It is sometimes associated with thunderstorms, but unlike lightning flashes arcing between two points, which last a small fraction of a second, ball lightning reportedly lasts many seconds. There have been some reports of production of a similar phenomenon in the laboratory, but some still disagree on whether it is the same phenomenon.

Contents

[edit] Reports

Ball lightning discharges were once thought to be rare occurrences. A 1960 paper reported that 5% of the US population reported having witnessed ball lightning.[1] Another study analyzed reports of 10,000 cases.[2]

Ball lightning is photographed very rarely, and details of witness accounts can vary widely. Many of the properties observed in ball lightning accounts conflict with each other, and it is very possible that several different phenomena are being incorrectly grouped together. It is also possible that some photos are fakes.

The discharges reportedly appear during thunderstorms, sometimes issuing from a lightning flash, but large numbers of encounters reportedly occur during good weather with no storms within hundreds of miles.

A report from an area of central Africa having a very high incidence of lightning said that ball lightning used to appear from a certain hill just before the onset of the rainy season.[3] (The report also exhibits a reluctance to report such phenomena typical of many people).

Ball lightning reportedly tends to float (or hover) in the air and take on a ball-like appearance. Its shape has been described as spherical, ovoid, teardrop, or rod-like with one dimension being much larger than the others. The longest dimension reported is between fifteen and forty centimeters. Many are red to yellow in colour, sometimes transparent, and some contain radial filaments or sparks. Other colours, such as blue or white occur as well.

Sometimes the discharge is described as being attracted to a certain object, and sometimes as moving randomly. After several seconds the discharge reportedly leaves, disperses, is absorbed into something, or, rarely, vanishes in an explosion.

A 19th Century depiction of ball lightning
A 19th Century depiction of ball lightning

Pilots in World War II described an unusual phenomenon for which ball lightning has been suggested as an explanation. The pilots saw small balls of light "escorting" bombers, flying alongside their wingtips. Pilots of the time referred to the phenomenon as "foo fighters," initially believing that the lights were from enemy planes. However there are other theories as to the identity of the foo fighters.

Other accounts place ball lightning as appearing over a kitchen stove or wandering down the aisle of an airliner[4]. One report described ball lightning following and engulfing a car, causing the electrical supply to overload and fail.[citation needed]

Some researchers suggest that ball lightning has a more diverse range of properties than previously thought (e.g. Singer, 1971). Japanese investigators (e.g. Ofuruton et al) report that Japanese ball lightning can occur in fine weather and be unconnected with lightning. The diameter is said to be typically 20-30 cm but sometimes even larger up to a few meters. Ball lightning can split and recombine and can exhibit large mechanical energy like carving trenches (e.g. Fitzgerald 1978) and holes into the ground. Ball lightning is also said to have an odd motion such as looping and the appearance of bouncing along the ground.

[edit] Historical accounts

One of the earliest and most destructive occurrences was reported to have taken place during The Great Thunderstorm at Widecombe-in-the-Moor, Devon, in England, on October 21, 1638. Four people died and around 60 were injured when what appeared to have been ball lightning struck a church.[citation needed]

A famous anecdote from 1753 depicts ball lightning as having violent potential. Professor Georg Richmann, of Saint Petersburg, Russia created a kite flying apparatus similar to that built by Benjamin Franklin a year earlier. He was attending a meeting of the Academy of Sciences, when he heard thunder. The Professor ran home with his engraver to capture the event for posterity. While the experiment was underway, ball lightning appeared, collided with Richmann's forehead and killed him, leaving a red spot. His shoes were blown open, parts of his clothes singed, the engraver knocked out; the doorframe of the room was split, and the door itself torn off its hinges.[5][6]

British occultist Aleister Crowley also reported witnessing what he referred to as "globular electricity" during a thunderstorm on Lake Pasquaney in New Hampshire in 1916. As related in his Confessions, he was sheltered in a small cottage when he "noticed, with what I can only describe as calm amazement, that a dazzling globe of electric fire, apparently between six and twelve inches in diameter, was stationary about six inches below and to the right of my right knee. As I looked at it, it exploded with a sharp report quite impossible to confuse with the continuous turmoil of the lightning, thunder and hail, or that of the lashed water and smashed wood which was creating a pandemonium outside the cottage. I felt a very slight shock in the middle of my right hand, which was closer to the globe than any other part of my body."[7]

On 30th April 1877, a ball of lightning entered the Golden Temple at Amritsar, India, and exited through a side door. This event was observed by a number of people, and the incident is inscribed on the front wall of Darshani Deodhi.

[edit] Analysis

An early attempt to explain ball lightning was recorded by Nikola Tesla in 1904. [8]

Difficult features of the lightning include its persistence and its near-neutral buoyancy in air. A popular hypothesis is that ball lightning is a highly ionized plasma contained by self-generated magnetic fields: a plasmoid.[citation needed] This hypothesis is not initially credible. If the gas is highly ionized, and if it is near thermodynamic equilibrium, then it must be very hot. Since it must be in pressure equilibrium with the surrounding air, it will be much lighter and hence float up rapidly. Magnetic fields, if present, might provide the plasmoid's coherence, but will not reduce this buoyancy. In addition, a hot plasma cannot persist for long because of recombination and heat conduction.

There may, however, be some novel form of plasma for which the above arguments do not fully apply. For example, a plasma may be composed of negative and positive ions, rather than electrons and positive ions. In that case, the recombination may be rather slow even at ambient temperature. One such theory involves positively charged hydrogen and negatively charged nitrites (NO2–) and nitrates (NO3–). In this theory, the role of the ions as seeds for the condensation of water droplets is important.[citation needed]

If ball lightning releases energy stored in chemical form, its persistence and neutral buoyancy might be more easily understood. The reaction might proceed slowly due to kinetic or geometric constraints, and the reaction could take place near ambient temperature. One of the first detailed theories of this sort involved the oxidation of nanoparticle networks formed when normal lightning strikes on soil.[9] A recently published experimental investigation of this effect by evaporating pure silicon with an electric arc reported producing "luminous balls with lifetime in the order of seconds".[10] Videos of this experiment are available online. [11] The coherence of the collection of nanoparticles may be enhanced by vortex motion, like that of a smoke ring.[12]

A proposed explanation[verification needed] for the numerous colours reported for ball lightning is the following known gas phase chemoluminescent reaction:

NO+O3 → NO2[◊]+ O2

Broadband visible light is emitted from the NO2 as it reverts to a lower energy state. This explanation is supported by the numerous witness accounts of the presence of ozone.

Other suggestions include:

  • that ball lightning is some form of induction phenomenon[citation needed] (electromagnetic knot), ball lightning having allegedly been witnessed inside metal aircraft.[13]
  • that it is an optical illusion similar to the aftereffect of a photographer's flash directed into a person's eyes. (This suggestion would tend to account for the reports of "ball lightning" persisting for various lengths of time, and of appearing to float within a room or other dwelling, etc.)[citation needed]

[edit] Esoteric explanations

Ball lighting has been connected to reports of several supernatural phenomena, ranging from will o' the wisps to UFOs. Some people believe the ball lightning phenomena are ghosts or spirits, or are related to poltergeists and spontaneous human combustion.[14] References can be seen in the will o' the wisp and other spirits that take the guise of orbs of light. Some UFO skeptics have suggested that many apparent close encounters are actually observations of ball lightning. UFO enthusiasts report seeing ball lightning often at crop circle sites and believe them to be some kind of intelligence or come from some kind of intelligence while not denying that it is indeed ball lightning.

Another esoteric explanation that has been offered for ball lightning is that it is the passage of microscopic primordial black holes through the Earth's atmosphere. No such tiny black holes have ever been positively detected, and it is uncertain whether they would have the physical properties described by ball lightning if they did in fact exist and in great enough quantity to account for ball lightning reports. This explanation also would not account for their alleged co-occurrence with electrical storms. However, inspired by accounts of ball lightning that, amongst other physically verifiable effects, had ploughed a 90-metre trench across peat bogs in Ireland, Pace Vandevender, a plasma physicist who worked until his retirement on thermonuclear fusion at Sandia National Laboratories in Albuquerque, New Mexico, believes that no explanation other than a black hole with a mass of more than 20 tonnes could explain the displacement of more than 100 tonnes of peat. His colleagues at Sandia agreed that crazy though the hypothesis seems, it was worthy of the attention of a national laboratory.[15]

[edit] Ball lightning in mythology and fiction

Among the ancients of Japanese mythology, there is a myth that ball lightning is the wrath of the thunder god, Raijin from Japanese mythology. In Basque mythology ball lightning were believed to be either main deity, Mari or Sugaar, travelling from one mountain to another. M. l'abbé de Tressan in, Mythology compared with history: or, the fables of the ancients elucidated from historical records,

...during a storm which endangered the ship Argo, fires were seen to play round the heads of the Tyndarides, and the instant after the storm ceased. From that time, those fires which frequently appear on the surface of the ocean were called the fire of Castor and Pollux. When two were seen at the same time, it announced the return of calm, when only one, it was the presage of a dreadful storm. This species of fire is frequently seen by sailors, and is a species of ignis fatuus. (page 417)

Some phenomena known from folklore, such as the will o' the wisp, may be related to ball lightning.

An early fictional reference to ball lightning appears in a children's book set in the 1800s by Laura Ingalls Wilder[16]. The books are considered historical fiction, but the author always insisted they were descriptive of actual events in her life. In Wilder's description, three separate balls of lightning appear during a winter blizzard near a cast iron stove in the family's kitchen. They are described as appearing near the stovepipe, then rolling across the floor, only to disappear as the mother (Caroline Ingalls) chases them with a willow-branch broom.[13]

Ball lightning also occurs in The Seven Crystal Balls, one of the books in The Adventures of Tintin series. In Stephen King's novella The Body, the narrator and his friends encounter this phenomenon traveling down railroad tracks just outside the fictional town of Castle Rock. A ball lightning named Skip makes a brief appearance as a character in Thomas Pynchon's novel Against the Day.

Fantasy fiction and games feature Ball Lightning as an attack spell cast by mage characters.

[edit] See also

[edit] Further reading

  • Barry, James Dale (1980). Ball Lightning and Bead Lightning. New York: Plenum Press. 
  • Cade, Cecil Maxwell; Delphine Davis (1969). The Taming of the Thunderbolts. New York: Abelard-Schuman Limited. 
  • Coleman, Peter F. (2004). Great Balls of Fire—A Unified Theory of Ball Lightning, UFOs, Tunguska and other Anomalous Lights. Christchurch, NZ: Fireshine Press. 
  • Golde, R. H. (1977). Lightning. Bristol: John Wright and Sons Limited. 
  • Golde, R. H. (1977). Lightning Volume 1 Physics of Lightning. Academic Press. 
  • Singer, Stanley (1971). The Nature of Ball Lightning. New York: Plenum Press. 
  • Stenhoff, Mark (1999). Ball Lightning, An Unsolved Problem in Atmospheric Physics. New York, Boston, Dordrecht, London, Moscow: Kluwer Academic/Plenum Publishers. 
  • Uman, Martin A. (1984). Lightning. Dover Publications. 
  • Viemeister, Peter E. (1972). The Lightning Book. Cambridge: MIT Press. 

[edit] References

  1. ^ Scientific American: "Ask the experts" website accessed 4 April 2007. The page refers to statistical investigations in J. R. McNally, "Preliminary Report on Ball Lightning" in Proceedings of the Second Annual Meeting of the Division of Plasma Physics of the American Physical Society, Gatlinburg, No. 2AD5 [1960], Paper J-15, pp. 1AD25).
  2. ^ Scientific American: "Ask the experts" website accessed 4 April 2007. This page quotes the work of A. I. Grigoriev, who analyzed more than 10,000 cases of ball lightning (A.I. Grigoriev, "Statistical Analysis of the Ball Lightning Properties," in Science of Ball Lightning, edited by Y. H. Ohtsuki, World Scientific Publishing Co., Singapore, 1988, pp. 88AD134).
  3. ^ The Northern Rhodesia Journal, Vol. 2, No. 3 (1954) pp. 79-80. Tim Cassidy: “Fireballs at Chisamba”. Accessed 26 February 2007.
  4. ^ "My husband was on a night flight years ago where he swears a "fireball" streaked down the aisle." [1]
  5. ^ Clarke, Ronald W. (1983). Benjamin Franklin, A Biography. Random House, 87. 
  6. ^ "Frenchman Thomas Francois D'Alibard used a 50-foot long vertical rod to draw down the "electric fluid" of the lightning in Paris on May 10, 1752. One week later, M. Delor repeated the experiment in Paris, followed in July by an Englishman, John Canton. But one unfortunate physicist did not fare so well. Georg Wilhelm Reichmann attempted to reproduce the experiment, according to Franklin's instructions, standing inside a room. A glowing ball of charge traveled down the string, jumped to his forehead and killed him instantly.[2]
  7. ^ Crowley, Aleister (1989-12-05). "Chp. 83", The Confessions of Aleister Crowley: An Autobiography. Penguin. ISBN 0140191895. 
  8. ^ Tesla, Nikola (1904-03-05). "The Transmission of Electrical Energy Without Wires". Electrical World and Engineer. 
  9. ^ John Abrahamson and James Dinniss, "Ball lightning caused by oxidation of nanoparticle networks from normal lightning strikes on soil", Nature 403:519-521 (3 Feb 2000).[3] See also the news story on p.487 of the same issue.
  10. ^ Paiva, Gerson Silva; Antonio Carlos Pavão, Elder Alpes de Vasconcelos, Odim Mendes, Jr., Eronides Felisberto da Silva, Jr. (2007). "Production of Ball-Lightning-Like Luminous Balls by Electrical Discharges in Silicon". Phys. Rev. Lett. 98. DOI:10.1103/PhysRevLett.98.048501. Retrieved on [[2007, 6 April]].  See also news stories: Lightning balls created in the lab, New Scientist, 10 January 2007, and Ball Lightning Mystery Solved? Electrical Phenomenon Created in Lab, National Geographic News, 22 January 2007
  11. ^ [4]
  12. ^ "Ball lightning explained", Australian Broadcasting Corporation, 2002-04-04. Also articles by Coleman in Weather and in the 2006 Journal of Scientific Exploration 20,2,215-238.
  13. ^ a b Getline, Meryl. "Playing with (St. Elmo's) fire", USA Today, 2005-10-17.
  14. ^ http://www.newscientist.com/article.ns?id=dn1720
  15. ^ New Scientist, Vol. 192, No. 2583/2584, pages 48-51.
  16. ^ Wilder, Laura Ingalls (1937). On the Banks of Plum Creek. Harper Trophy. 

[edit] External links

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