Ball lightning

Ball lightning is an atmospheric electrical phenomenon, the physical nature of which is still controversial. The term refers to reports of luminous, usually spherical objects which vary from pea-sized to several meters in diameter. It is sometimes associated with thunderstorms, but unlike lightning flashes, which last only a fraction of a second, ball lightning reportedly lasts many seconds. Laboratory experiments have produced effects that are visually similar to reports of ball lightning, but it is presently unknown whether these are actually related to any naturally occurring phenomenon.Scientific data on natural ball lightning is scarce due to its infrequency and unpredictability. The presumption of its existence is based on reported public sightings, and has therefore produced somewhat inconsistent findings. Due to inconsistencies and the lack of reliable data, the true nature of ball lightning is still unknown. [http://www.abc.net.au/science/articles/2008/03/20/2194630.htm?site=science&topic=latest ABC.net.edu: "Ball lightning bamboozles physicist"] ] Until recently, ball lightning was often regarded as a fantasy or a hoax.cite web|url=http://www.newscientist.com/article.ns?id=dn1720|title=Ball lightning scientists remain in the dark|date=20 December 2001|publisher=New Scientist] Reports of the phenomenon were dismissed due to lack of physical evidence, and were often regarded the same way as UFO sightings. Recently however, the overwhelming number of sightings has caused a renewed interest in studying its existence.

Natural ball lightning appears infrequently and unpredictably, and is therefore rarely (if ever truly) photographed. However, several purported photos and videos exist. Perhaps the most famous story of ball lightning unfolded when 18th-century physicist Georg Wilhelm Richmann installed a lightning rod in his home and was struck in the head - and killed - by a "pale blue ball of fire."cite web|url=http://www.economist.com/science/displaystory.cfm?story_id=10918140|title=Great balls of fire!|date=27 March 2008|publisher="The Economist" ]

Historical accounts

The Great Thunderstorm

One of the earliest and most destructive occurrences was reported during The Great Thunderstorm at a church in Widecombe-in-the-Moor, Devon, in England, on 21 October 1638. Four people died and approximately 60 were injured, when during a severe storm, an 8' ball of fire struck and entered the church, nearly destroying it. Large stones from the church walls were hurled into the ground and through large wooden beams. The ball of fire smashed the pews and many windows, and filled the church with a foul sulfurous odor and dark, thick smoke.

The ball of fire reportedly split in two, one exiting through a window by smashing it open, the other disappearing somewhere inside the church. The explanation at the time, because of the fire and sulfur smell, was that the ball of fire was "the devil" or the "flames of hell". Later, some blamed the entire incident on two people who had been playing cards in the pew during the sermon, whom they say must have invoked God's wrath. [cite book|url=http://books.google.com/books?id=nBFJAAAAMAAJ&pg=PR8&dq=Wykes+Rothwell#PPR12,M1|title=Devon Notes and Queries|first=Peter Fabyan Sparke|last=Amery|coauthors=John S. Amery, Joshua Brooking Rowe]

Georg Richmann

A report from 1753 depicts ball lightning as being lethal, when Professor Georg Richmann of Saint Petersburg, Russia, created a kite flying apparatus similar to the one built by Benjamin Franklin a year earlier. He was attending a meeting of the Academy of Sciences when he heard thunder, and 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.

The ball left a red spot on Richmann's forehead, his shoes were blown open, and parts of his clothes singed. His engraver was knocked unconscious. The doorframe of the room was split, and the door itself torn from its hinges. [cite book|last=Clarke|first=Ronald W.|title=Benjamin Franklin, A Biography|publisher=Random House|year=1983|pages=87] ["Frenchman Thomas Francois D'Alibard used a convert|50|ft|m|0|sing=on 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. [http://www.physicstoday.org/vol-59/iss-1/p42.html] ]

Tsar Nicholas II

Tsar Nicholas II, the last Emperor of Russia, reported witnessing what he called "a fiery ball" while in the company of his grandfather, Tsar Alexander II: "Once my parents were away," recounted the Tsar, "and I was at the all-night vigil with my grandfather in the small church in Alexandria. During the service there was a powerful thunderstorm, streaks of lightning flashed one after the other, and it seemed as if the peals of thunder would shake even the church and the whole world to its foundations. Suddenly it became quite dark, a blast of wind from the open door blew out the flame of the candles which were lit in front of the iconostasis, there was a long clap of thunder, louder than before, and I suddenly saw a fiery ball flying from the window straight towards the head of the Emperor. The ball (it was of lightning) whirled around the floor, then passed the chandelier and flew out through the door into the park. My heart froze, I glanced at my grandfather - his face was completely calm. He crossed himself just as calmly as he had when the fiery ball had flown near us, and I felt that it was unseemly and not courageous to be frightened as I was....After the ball had passed through the whole church, and suddenly gone out through the door, I again looked at my grandfather. A faint smile was on his face, and he nodded his head at me. My panic disappeared, and from that time I had no more fear of storms." [http://www.orthodox.net/russiannm/nicholas-ii-tsar-martyr-and-his-family.html]

Aleister Crowley

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."cite book|chapterurl=http://www.hermetic.com/crowley/confess/chapter83.html|first=Aleister|last=Crowley|title=The Confessions of Aleister Crowley: An Autobiography|chapter=Chp. 83|url=http://www.hermetic.com/crowley/confess/index.html|id=ISBN 0140191895|publisher=Penguin|date=1989-12-05]

Other accounts

* On 30 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. [ [http://www.sikhpoint.com/religion/sikhhistory/MainEvents/miracle.htm Anandpur Sahib Resolution ] ]

* 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 moving in strange trajectories, which came to be referred to as foo fighters.

* Submariners in WWII gave the most frequent and consistent accounts of small ball lightning in the confined submarine atmosphere. There are repeated accounts of inadvertent production of floating explosive balls when the battery banks were switched in/out, especially if mis-switched or when the highly inductive electrical motors were mis-connected or disconnected. An attempt later to duplicate those balls with a surplus submarine battery resulted in several failures and an explosion. [ [http://www.peter-thomson.co.uk/tornado/fusion/Ball_lightning_and_the_charge_sheath_vortex.html Ball lightning - and the charge sheath vortex ] ]

* On 6 August 1994 a ball of lightning went through a closed window in Uppsala, Sweden, leaving a circular hole with a diameter of 5 centimeters. The incident was witnessed by residents in the area, and was recorded by a lightning strike tracking system on the Division for Electricity and Lightning Research at Uppsala University. [cite web|url=http://www.hvi.uu.se/Lightning/blixtar/Klotblixt.html|language=Swedish|publisher=Uppsala University|title=Ett fenomen som gäckar vetenskapen|first=Anders|last=Larsson|date=2002-04-23|accessdate=2007-11-19] [cite web|url=http://www.dn.se/DNet/jsp/polopoly.jsp?d=537&a=179865&viewAll=true|publisher=Dagens Nyheter|language=Swedish|date=9 September 2003|title=Finns det klotblixtar?|accessdate=2007-11-19]

Inconsistent characteristics

Depending on the report, ball lightning can move upwards as well as downwards, sideways, or in odd trajectories such as rocking from side to side like a falling leaf. It can move with or against the wind, or simply hover, more or less stationary in the air. Sometimes it is described as being attracted to houses, cars, persons, or other objects, [ [http://www.ernmphotography.com/Pages/Ball_Lightning/BL_Info_10.html BL_Info_10 ] ] but sometimes the balls are reportedly repelled or are unaffected by objects. Some accounts claim the balls have passed freely through solid masses, such as wood or metal, without any effect on the ball or material, while other accounts report damage to the material, such as melting or burning. Some reports suggest an attraction to, or even an origination from electric power lines. [ [http://amasci.com/weird/unusual/blold2.html Unusual Phenomea Reports: Ball Lightning ] ]

Ball lightning has been reported in many different colors, sometimes even transparent or translucent. It is sometimes said to contain radial filaments or sparks while others are evenly lit, and some have flames protruding from the ball surface. Its shape has been described as spherical, oval, tear-drop, or rod-like.

It has sometimes been reported during thunderstorms, sometimes issuing from a lightning flash, while sometimes it appears during calm weather with no storms in the vicinity.

The balls have been reported to disperse in many different ways, such as suddenly vanishing, gradually dissipating, absorption into an object, "pop"ing, exploding loudly, or even exploding with force, which is sometimes reported as damaging. Some accounts say the balls are lethal, killing on contact, while other accounts claim that they are harmless.

Laboratory experiments

Scientists have long attempted to produce ball lightning in laboratory experiments. While some experiments have produced effects that are visually similar to reports of natural ball lightning, it has not yet been determined whether there is actually any correlation.

Nikola Tesla reportedly was able to artificially produce ~1.5" balls, but he was really interested in higher voltages and powers, and remote transmission of power, so the balls he made were just a curiosity. [Tesla, Nikola (1978). "Nikola Tesla - Colorado Springs Notes 1899-1900". Nolit (Beograd, Yugoslavia), 368-370. ISBN-13: 978-0913022269]

There is a scientific group that holds a regular symposium on ball lightning, called the "International Symposium on Ball Lightning" or ISBL: [http://home.wxs.nl/~icblsec/isbl99/reportantwerp.html 1999] , [http://www.umsl.edu/~handelp/BLConference.html 2001] , [http://home.planet.nl/~icblsec/noscript.html 2004 & 2006] . The next symposium will take place in Kaliningrad, Russia in 2008. [http://plasma.karelia.ru/events/info/isbl2008.doc] A related group uses the generic name "Unconventional Plasmas". [ [http://home.planet.nl/~icblsec/frameset.html?pg_start.html ISBL'01 International Symposium on Ball Lightning ] ]

Water discharge experiments

Some scientific groups, including the Max Planck Institute, have reportedly produced a ball lightning-type effect by discharging a high-voltage capacitor in a tank of water. [ [http://www.cosmosmagazine.com/node/334 'Ball lightning' created in German laboratory | COSMOS magazine ] ] [http://www.jstage.jst.go.jp/article/pfr/1/0/039/_pdf]

Home microwave oven experiments

Many modern experiments involve using a microwave oven to produce small rising glowing balls, often referred to as "plasma balls".

Generally, the experiments are conducted by placing a lit or recently extinguished match or other small object in an ordinary microwave oven. The burnt portion of the object flares up into a large ball of fire, while the "plasma balls" can be seen floating around the ceiling of the oven chamber. The effect is caused by electricity arcing between the conductive carbon particles in the soot, similar to the way electricity arcs between the tines of a fork. This can damage the oven by leaving burn marks and causing high voltage electrical discharge back into the magnetron.

Some experiments describe covering the lit object with an inverted glass jar, which contains both the flame and the balls so they won't damage the chamber walls. Some experimenters have posted instructions, photos, and videos of these experiments. [ [http://jlnlabs.online.fr/plasma/gmr/index.htm How to make a Stable Plasmoid ( Ball Lightning ) with the GMR ( Graphite Microwave Resonator ) by Jean-Louis Naudin ] ] [ [http://www.angelfire.com/electronic/cwillis/microwave.html ball lightning in microwave ovens ] ] [ [http://www.powerlabs.org/uwavexp.htm#%A0%20Ball%20Lightning: POWERLABS's Microwave Experiments Page! ] ]

ilicon experiments

Some more recent experiments in 2007 involve shocking silicon wafers with electricity, which vaporizes the silicon and induces oxidation in the vapors. The visual effect can be described as small glowing, sparkling orbs that roll around a surface. Two Brazilian scientists, Antonio Pavão and Gerson Paiva of the Federal University of Pernambuco [ [http://www.ufpe.br/ Universidade Federal de Pernambuco ] ] have reportedly consistently made small long-lasting balls using this method. [ [http://www.ufpe.br/new/visualizar.php?id=5005 Pesquisadores da UFPE geram, em laboratório, fenômeno atmosférico conhecido como bolas luminosas ] ] [ [http://news.nationalgeographic.com/news/2007/01/070122-ball-lightning_2.html Ball Lightning Mystery Solved? Electrical Phenomenon Created in Lab ] ] These experiments stemmed from the theory that ball lightning is actually oxidized silicon vapors "(see vaporized silicon hypothesis, below)".

Possible scientific explanations

An early attempt to explain ball lightning was recorded by Nikola Tesla in 1904, [cite journal|last=Tesla|first=Nikola|authorlink=Nikola Tesla|url=http://web.archive.org/web/20051222121927/http://tfcbooks.com/tesla/wireless01.htm|title=The Transmission of Electrical Energy Without Wires|journal=Electrical World and Engineer|date=1904-03-05] but currently, there is no widely accepted explanation of what exactly ball lightning is. Several theories have been advanced, however, since the phenomenon was brought into the scientific realm by the French Academy scientist François Arago. [François Arago, "Meteorological Essays" by , Longman, 1855]

Vaporized silicon hypothesis

This hypothesis suggests that ball lightning consists of vaporized silicon burning through oxidation. When lightning strikes earth's silica-rich soil, the silicon could be instantly vaporized, the vapor itself condensing and burning slowly via the oxygen in the surrounding air. 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". [cite journal |last=Paiva |first=Gerson Silva |coauthors=Antonio Carlos Pavão, Elder Alpes de Vasconcelos, Odim Mendes, Jr., Eronides Felisberto da Silva, Jr.|year= 2007|title= Production of Ball-Lightning-Like Luminous Balls by Electrical Discharges in Silicon|journal=Phys. Rev. Lett.|volume=98 |doi=10.1103/PhysRevLett.98.048501|accessdate=2007-04-06 |pages=048501] [cite news|url=http://www.newscientist.com/article.ns?id=mg19325863.500|title=Lightning balls created in the lab|publisher=New Scientist|date=10 January 2007] [cite news|url=http://news.nationalgeographic.com/news/2007/01/070122-ball-lightning.html|title=Ball Lightning Mystery Solved? Electrical Phenomenon Created in Lab|publisher=National Geographic News|date=22 January 2007] Videos of this experiment have been made available. [ [ftp://ftp.aip.org/epaps/phys_rev_lett/E-PRLTAO-98-047705/] ]

Nanobattery hypothesis

Another current hypothesis published by Oleg Meshcheryakov suggests that ball lightning is made of composite nano or submicrometre particles, each particle constituting a battery. A surface discharge shorts these batteries, resulting in a current which forms the ball. His model is described as an aerosol, but not aerogel, model that explains all the observable properties and processes of ball lightning. [cite journal |last=Meshcheryakov|first=Oleg |year= 2007|title=Ball Lightning–Aerosol Electrochemical Power Source or A Cloud of Batteries|journal=Nanoscale Res. Lett.|volume=2 |issue=3|doi=10.1007/s11671-007-9068-2|url=http://www.springerlink.com/content/501k0653122j172u/fulltext.pdf|accessdate=2007-06-27 |pages=319] [cite news|url=http://www.eetimes.com/showArticle.jhtml;jsessionid=QHGIIZHBKYF0KQSNDLPSKH0CJUNN2JVN?articleID=201802939|title=Ball lightning's frightening . . . but finally explained
publisher=EE Times|date=29 August 2007]

Black hole hypothesis

Yet another hypothesis is that some extreme ball lightning is actually the passage of microscopic primordial black holes through the Earth's atmosphere. Inspired by M. Fitzgerald’s account of ball lightning on August 6, 1868, in Ireland that lasted 20 minutes and left a 6 meter square hole, a 90 meter long trench, a second trench 25 meters long, and a small cave in the peat bog, Pace VanDevender, a plasma physicist at Sandia National Laboratories in Albuquerque, New Mexico, and his team found depressions consistent with Fitzgerald’s report and inferred that the evidence is inconsistent with thermal (chemical or nuclear) and electrostatic effects. An electromagnetically levitated, compact mass of >20,000 kg would produce the reported effects but requires a density of > 2000 times the density of gold, which implies a mini black hole. He and his team found a second event in the peat-bog witness plate from 1982 and are currently trying to geolocate electromagnetic emission consistent with the hypothesis. His colleagues at the institute agreed that, crazy though the hypothesis seemed, it was worthy of their attention. [cite journal|url=http://www.newscientist.com/channel/fundamentals/mg19225831.700-blackholes-in-your-backyard.html|journal=New Scientist|volume=192|issue=2583/2584|pages=48–51|title=Blackholes in your backyard|first=Hazel|last=Muir|date=23 December 2006|doi=10.1016/S0262-4079(06)61459-0]

Other hypotheses

There also are many other hypotheses put forth to explain ball lightning, such as:

# Spinning electric dipole hypothesis. (Endean (1976) published this hypothesis. He postulated that ball lightning could be described as an electric field vector spinning in the microwave frequency region.)
# Electrostatic Leyden jar models. (Singer (1971) discusses this type of hypothesis and suggested that the electrical recombination time would be too short for the ball lightning lifetimes often reported.)
# J. Pace VanDevender separates extreme ball lightning of the highly energetic violent kind, and proposes a theory of neutrinos and heavy neutrinos. [ [http://www.thunderbolts.info/webnews/ieee_plasma_balllightening.htm The IEEE, Plasma Cosmology and Extreme Ball Lightning ] ]
# Nuclear hypotheses
# Trapped microwave hypotheses
# Maser hypothesis
# Fractal aerogel hypotheses (Smirnov (1987) put forward a charged aerosol cluster theory.)
# Magnetically trapped plasma theories
# Vortex hypotheses (Coleman (2006) described ball lightning as a vortex fireball or natural vortex burning a combustible fuel. Ball lightning under this theory is essentially a turbulent swirling flame inside a vortex.
# Atmospheric Rydberg matter hypotheses
# Anti-matter hypotheses
# Optical illusions.
# Hallucinations associated with epileptic seizures (Cooray and Cooray (2008) show that the features of hallucinations experienced by patients having seizures in the occipital lobe are remarkably similar to the observed features of ball lightning. The study also shows that the rapidly changing magnetic field of a close lightning flash has a strength which is large enough to excite the neurons in the brain strengthening the possibility of lightning induced seizure in the occipital lobe of a person located close to a lightning strike establishing the connection between epileptic hallucination mimicking ball lightning and thunderstorms [http://www.el.angstrom.uu.se/meny/artiklar/ball%20lightning.pdf]
# 4 dimensional ring hypotheses: According to a Hungarian scientist, György Egely, ball lightnings come in pairs in our 3 dimension as they are the intersections of a 4 dimensional ring of charged particles staying together with the same way lightning itself does. With this he explains its extreme energy density, extreme energy transfer and that about the half (Egely himself made one of the largest statistics about ball lightning cases.) of the ball lightnings disappear without any sign, and some of them appear from nowhere without any source of energy. In his book Egely stated some extreme cases clearly validating this theory: Among others one in which the ball lightning exploded boiling a large tank of water so fast that the energy needed couldn't be transferred through its visually observed size, and one in which a ball lightning electrocuted people inside an EM shielded room by exploding outside. He stated that to make the energy distribution reasonable in each cases, the explosion had to happen outside of our 3 dimensions. [Egely György: A kulcs a negyedik dimenzióban (1988)]

Esoteric explanations

Ball lightning 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. 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 lightningFact|date=August 2008.

In popular culture

Mythology

* Among the ancients of Japanese mythology, there is a myth that ball lightning is the wrath of the thunder god, Raijin.

* In Basque mythology ball lightning were believed to be either main deity, Mari or Sugaar, traveling 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)

Literature

An early fictional reference to ball lightning appears in a children's book set in the 19th century by Laura Ingalls Wilder. [cite book|first=Laura Ingalls|last=Wilder|authorlink=Laura Ingalls Wilder|title=On the Banks of Plum Creek|publisher=Harper Trophy|year=1937] 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.cite news|last=Getline|first=Meryl|url=http://www.usatoday.com/travel/columnist/getline/2005-10-17-ask-the-captain_x.htm|title=Playing with (St. Elmo's) fire|publisher=USA Today|date=2005-10-17]

In Dean Koontz's novel Dark Rivers of the Heart, the protagonist encounters Ball lightning while traveling through the Mojave desert.

Film

* In the Russian film "Burnt by the Sun" a crackling lightning ball appears at several key moments throughout the picture. It passes through rooms, sometimes causing damage, like cracking the glass covering family photographs at the end of the feature. At one point, it explodes in the forest, setting a tree on fire.

See also

* St. Elmo's fire
* Naga fireballs
* Hessdalen light
* Will o' the wisp
* Foo fighter
* Red sprite
* Marfa lights

Further reading

References

External links

* [http://www.youtube.com/watch?v=zM6NLKY2SHk An example of a youtube microwave plasma ball experiment.]
* [http://www.torro.org.uk/TORRO/research/blightning.php Lethality of ball lightning]
*cite web|last=Meshcheryakov|first=Oleg|url=http://www.springerlink.com/content/501k0653122j172u/fulltext.pdf|title=Ball Lightning–Aerosol Electrochemical Power Source or A Cloud of Batteries|publisher=Nanoscale Res Lett (2007) 2:319–330
*cite web|last=Aspden|first=Harold|url=http://www.aspden.org/papers/bib/1983a.htm|title=The Thunderball - an Electrostatic Phenomenon|publisher=Inst. Phys. Conf. Ser. No. 66: Session VI, Electrostatics 1983, Oxford, pp. 179–184, 1983
*cite web|last=Beaty|first=Bill|url=http://www.amasci.com/tesla/ballgtn.html|title=Ball Lightning Page and cite web|url=http://amasci.com/weird/unusual/bl.html|title=Eyewitness reports — Various articles, experiments, and information on Ball lightning
*cite web|last=Bergström|first=Arne|url=http://hem.passagen.se/scientor/|title=Electrodynamic confinement -- a new field of science and technology?|publisher=Scientor Research & Development|location=Stockholm, Sweden — the secret of ball lightning and a new field of science and technology
*cite web|last=Darling|first=David|url=http://www.daviddarling.info/encyclopedia/B/ball_lightning.html|title=Ball lightning|publisher=The Encyclopedia of Astrobiology, Astronomy, and Spaceflight.
*cite web|last=Corum|first=Kenneth L.|coauthors=James F. Corum|url=http://home.dmv.com/~tbastian/ball.htm|title=Tesla's production of electric fireballs|publisher=Corum & Associates, Inc.|location=Windsor, Ohio
*cite web|last=Hochwald|first=Hans|title='Ball Lightning' produced using a high voltage arc and carbon|url=http://apache.airnet.com.au/~fastinfo/microwave/highvoltage/ — Alternative "toaster" Microwave Experiments
*cite web|last=Shelton|first=J. D.|url=http://www.geocities.com/jaydshelton/|title=Eddy Current Model of Ball Lightning|location=Fruita, Colorado|date=2004-01-13
*cite web|last=Talbot|first=Michel T.|url=http://www.maxpages.com/mapit/BALL_LIGHTNING|title=Ball Lightning: Rare Atmospheric Phenomena (RAP)
*cite web|url=http://www.straightdope.com/columns/040917.html|publisher=Straight Dope|title=Does ball lightning really exist?
*cite web|url=http://www.electronpowersystems.com/Images/Ball%20Lightning%20Explained.pdf|title=Ball Lightning as a Stable Toroid|format=pdf
*cite web|url=http://www.skepdic.com/balllightning.html|title=Skeptic's Dictionary information on ball lightning, with further links
*cite web|url=http://www.liveleak.com/view?i=3b5_1195270177|title=Ball lightning footage from LiveLeak

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Ball lightning — Lightning Light ning (l[imac]t n[i^]ng), n. [For lightening, fr. lighten to flash.] 1. A discharge of atmospheric electricity, accompanied by a vivid flash of light, commonly from one cloud to another, sometimes from a cloud to the earth. The… … The Collaborative International Dictionary of English
ball lightning — n. a rare form of lightning seen as a short lived, reddish, glowing ball, up to about a foot in diameter, that appears to float in the air or move rapidly along the ground before disintegrating … English World dictionary
ball lightning — a rare form of lightning, consisting of a bright, luminous ball that moves rapidly along objects or floats in the air. Also called globe lightning. [1855 60] * * * ▪ atmospheric phenomenon also called globe lightning a rare aerial… … Universalium
ball lightning — Fireball Fire ball , n. 1. (Mil.) A ball filled with powder or other combustibles, intended to be thrown among enemies, and to injure by explosion; also, to set fire to their works and light them up, so that movements may be seen. [1913 Webster]… … The Collaborative International Dictionary of English
ball lightning — kamuolinis žaibas statusas T sritis fizika atitikmenys: angl. ball lightning; fireball; globular lightning vok. Kugelblitz, m rus. шаровая молния, f pranc. éclair sphérique, m; foudre en boule, f; foudre globulaire, f … Fizikos terminų žodynas
ball lightning — kamuolinis žaibas statusas T sritis ekologija ir aplinkotyra apibrėžtis Švytintis, kartais kibirkščiuojantis 10–20 cm skersmens ugnies kamuolys, susidarantis dažniausiai po linijinio žaibo. Išsilaiko nuo 1 iki keleto minučių, juda be garso, per… … Ekologijos terminų aiškinamasis žodynas
ball lightning — noun Date: 1857 a rare form of lightning consisting of luminous balls that may move along solid objects or float in the air … New Collegiate Dictionary
ball lightning — noun a rare form of lightning in the shape of a moving luminous globe … English new terms dictionary
ball lightning — noun : an extremely rare form of lightning consisting of highly luminous balls that move with moderate speed and usually disappear without an explosion … Useful english dictionary
ball lightning — noun A short lived, glowing ball sometimes observed to float in the air; thought to consist of ionized gas associated with thunderstorms … Wiktionary

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