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For other uses, see Ball lightning (disambiguation).

Ball lightning reportedly takes the form of a short-lived, 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 1 Reports 1.1 Historical and fictional accounts 2 Laboratory experiments 3 Analysis 4 Esoteric explanations 5 Quotations 6 See also 7 Further reading 8 References 9 External links

[edit] Reports

Ball lightning discharges were once thought to be extremely rare occurrences, but recent research shows that a few percent of the US population have been witnesses.<ref>"At one time BL was thought to be extremely rare, but this was because most BL eyewitnesses feared ridicule and wouldn't come forward. In reality, five percent of the population has seen BL close up." [1] </ref> Surveys have been taken of eyewitness accounts by at least 3000 people.^{[citation needed]}

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.

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.

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<ref>"My husband was on a night flight years ago where he swears a "fireball" streaked down the aisle." [2] </ref>. One report described ball lightning following and engulfing a car, causing the electrical supply to overload and fail.^{[citation needed]}

[edit] Historical and fictional accounts

One of the earliest reported, and most destructive, occurrences is said 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]}

Another reference to ball lightning appears in a children's book set in the 1800s by Laura Ingalls Wilder<ref>Wilder, Laura Ingalls (1937). On the Banks of Plum Creek. Harper Trophy.</ref>. 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 chases them with a willow-branch broom.<ref name="GetlinePlaying">Getline, Meryl. "Playing with (St. Elmo's) fire", USA Today, 2005-10-17.</ref>

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 instand 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 Pullux. 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)

Notorious 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."<ref name="AleisterCrowley">Crowley, Aleister (1989-12-05). “Chp. 83”, The Confessions of Aleister Crowley: An Autobiography. Penguin. ISBN 0140191895.</ref>

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 head 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.<ref>Clarke, Ronald W. (1983). Benjamin Franklin, A Biography. Random House, 87.</ref><ref>"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.[3] </ref>

Ball lightning also occurs in The Seven Crystal Balls. This is 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.

[edit] Laboratory experiments

Many attempts have been made over the years to produce ball lightning in the laboratory, but it is easy to mistake other phenomena for ball lightning. Most prominent among these are glowing spheres produced by high-energy arcs between metal electrodes. Such arcs often expel small droplets of molten metal that are heated to extremely high temperatures. Because of their high heat content, these droplets will continue to glow quite brightly for several seconds after landing on a floor or other surface, and their odd physical characteristics can cause them to roll, still glowing brightly, for some distance after landing. They thus mimic the most common description of ball lightning before cooling down into a small speck of metallic dust. The most familiar instance of these glowing spheres is the "weld spatter" usually seen during arc welding operations. The spheres can also be produced when a switch carrying very large electric currents is operated improperly, or during certain grinding or other machining operations.

Some laboratory experiments claim to have produced ball lightning, but there is no rigorous confirmation that the phenomenon reproduced is related to the natural one. The natural occurrences are, by their nature, difficult to document accurately. Consequently, many scientists continue to dispute the existence of ball lightning as a distinct physical phenomenon.<ref>Singer, Stanley (2002). "Ball lightning: the scientific effort". Phil. Trans. R. Soc. London v360: 5-9.</ref> In one such occurrence, support staff at the Cavendish Laboratory, Cambridge reported ball lightning during a thunderstorm; their account was written up without speculation by Brian Pippard, the Head of Department, in the journal Nature.<ref>Pippard, A. B. (1982). "Ball of Fire?". Nature v298: 702.</ref>

In February 2006, scientists at Tel Aviv University claimed to have produced ball lightning in the lab using a microwave drill and ceramic substrate.<ref>"Great balls of lightning", Physics Web, 2006-02-09.</ref>. More recently (June, 2006) researchers at the Max Planck Institute for Plasma Physics successfully recreated the phenomenon using a relatively simple water tank experiment. The experiment involves two electrodes placed in a small tank of salt water, with one electrode covered by a clay tube. A large current of over 60 amps was then run through the water for 150 milliseconds, vaporizing water inside the clay tube and causing a ball of plasma to appear above the tank for 0.3 seconds. Although the plasma glows brightly it was found to be quite cold, much like a neon tube <ref>Max Planck Institute, Berlin, 7 June 2006</ref>.

[edit] Analysis

An early attempt to explain ball lightning was recorded by Nikola Tesla in 1904. <ref>Tesla, Nikola (1904-03-05). "The Transmission of Electrical Energy Without Wires". Electrical World and Engineer.</ref>

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]}

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.

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. Other suggestions include:

• that ball lightning may represent the missing science of burning natural vortices. This theory by Coleman was published in Weather and in the 2006 Journal of Scientific Exploration 20,2,215-238.
• that some stored chemical energy is slowly being released. see Abrahamson, J. and J. Dinniss (2000). Ball lightning caused by oxidation of nanoparticle networks from normal lightning strikes on soil. Nature 403:519-521.
• that ball lightning is some form of induction phenomenon (electromagnetic knot), ball lightning having allegedly been witnessed inside metal aircraft.<ref name="GetlinePlaying"/>
• that the lightning is a Hill's vortex, like a smoke ring.<ref>"Ball lightning explained", Australian Broadcasting Corporation, 2002-04-04.</ref>
• that it is an optical illusion similar to the aftereffect of a photographer's flash directed into a person's eyes.<ref>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. The commonly shared modern experience of such flashes directly related to flash-photographs, and present-day research of optical perception and neuro-ophthalmology, provides yet another possibility to add to the many hypotheses that have historically been proposed.</ref>^{[citation needed]}
• There is also a theory that the phenomena called "poltergeists" and "human combustions" might be subdivisions of ball lightning phenomena http://www.newscientist.com/article.ns?id=dn1720

[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. 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 exotic 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.

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.

[edit] Quotations

"...Our conclusion is that these fireballs are primarily RF in origin, and not nuclear phenomena..." - Corum

"...No theory of ball lightning exists which can account for both the degree of mobility that the ball exhibits and for the fact that it does not rise...." - Talbot

[edit] See also

• St. Elmo's fire
• Naga fireballs
• Hessdalen light
• Spooklight
• Will o' the wisp
• Kiril Chukanov
• Foo fighter
• Red sprite

[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

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[edit] External links

• Bergström, Arne. Electrodynamic confinement -- a new field of science and technology?. Scientor Research & Development. — the secret of ball lightning and a new field of science and technology
• Corum, Kenneth L.; James F.Corum. Tesla's production of electric fireballs. Corum & Associates, Inc..
• Talbot, Michel T.. Ball Lightning : Rare Atmospheric Phenomena (RAP).
• Beaty, Bill. Ball Lightning Page. and Eyewitness reports. — Various articles, experiments, and information on Ball lightning
• Hochwald, Hans. 'Ball Lightning' produced using a high voltage arc and carbon. — Alternative "toaster" Microwave Experiments
• Darling, David. Ball lightning. The Encyclopedia of Astrobiology, Astronomy, and Spaceflight..
• Shelton, J. D. (2004-01-13). Eddy Current Model of Ball Lightning.
• Does ball lightning really exist?. Straight Dope.
• Ball lightning properties.
• Ball Lightning as a Stable Toroid (pdf).
• The Physical Theory of Ball Lightning (pdf).
• Sceptic's Dictionary information on ball lightning, with further links.

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