AN INTERPRETATON OF BALL LIGHTNING
(June 2024)
ABSTRACT
We explain the physics of a ball lightning with the physics of arc light. Similar atmospheric phenomena may be the corona discharge and the aurora borealis. The colour of arc light is also caused by ionised oxygen and nitrogen atoms. In the lucky case, the lines of oxygen and nitrogen can be measured in the spectrum of the ball lightning. Nitrogen oxides are formed by heat, during lightning - and atmospheric arc-light - nitrogen is naturally oxidised to form nitrogen oxides with a characteristic odour, as observed. Thermal ionisation is typical of arc-light, and in the case of corona discharge, collision ionisation is typical of ground-ground ionisation. Both types of ionisation are caused by the negative resistivity (dynamic resistance, which does not exist at zero voltage) state of the plasma, which is considered to be the stability condition of the spherical filament. In the negative-resistance state, the current, i.e. the number of ions, increases as the voltage decreases, and the current is limited only by the conservation laws.
The formation of the ball lightning: Stationary ion channels from the Earth are difficult to spot, can only be detected in high-speed camera images, and are not part of cloud lightning. When atmospheric electric potential is tens of thousands of volts per centimetre, they ionise oxygen and nitrogen in the air. Stationary ion channels from the Earth are made up of ionised oxygen and nitrogen atoms. The source of the ball lightning is thought to be these ion channels from the Earth. If the atmospheric tension is sufficiently high, and if a sufficient number of ions are created, a negative-resistance state of the ion channel is formed, known as a glowing ember, or corona discharge. In corona discharge, the electron avalanches cause collisional ionisation. The process is self-excited and a negative resistive state is created, which increases the intensity of the electron avalanches even at decreasing voltages: the channel sometimes becomes independent of the external voltage, the ground surface, and a ball lightning is formed: a negative resistive state, then characterised by thermal emission. Thermal emission increases the mobility of the particles, allowing the plasma to float freely.
The negative resistance phenomenon of arc light is the explanation for the stability of the spherical lightning. Thermal emission is most intense in the centre of the sphere, which is the cause of the inflating spherical shape. The surface has a lower temperature, is characterised by glowing embers, and the ions recombine at the rim.
The negative resistance phenomenon of arc light is the explanation for the stability of the spherical lightning. Thermal emission is most intense in the centre of the sphere, which is the cause of the inflating spherical shape. The surface has a lower temperature, is characterised by glowing embers, and the ions recombine at the rim.
Proposed theoretical experiment: a small piece of metal is annealed (e.g. with a laser) at a temperature where thermal ionisation occurs. If the light source shows some stability in the presence of flowing air, it is conclusive.
INTRODUCTION
The research tool was an internet search, a nice little demo video: https://www.youtube.com/watch?v=1bBNeyrMOJE There are many explanations* of spherical lightning covering many topics in physics. The hypotheses assume central force fields, or rarely occurring particles, there is no generally accepted description of spherical lightning, an atmospheric phenomenon. We hypothesise that the ions and electrons in the air that make up the ball lightning can be described by the phenomena of gas discharges.
Literature review*: ball lightning is not a common phenomenon, many explanations have been published but not generally accepted. On atmospheric and lightning physics, see R.P. Feynman-R.B. Leighton-M. Sands, Modern Physics, vol. 5, (p. 120, Technical Publishers, 1969. ETO 53 "19" (082)), where the authors summarize the physics of lightning in the chapter "Atmospheric Electricity". The atmospheric electric potential can be tens of thousands of volts per centimeter, which ionizes oxygen and nitrogen. The real difference in the literature hypotheses is in the quality of the charged particles and the origin of the central force fields that hold them together.
Corona discharge is a similar, colourful, nearly spherical atmospheric ionisation phenomenon, the source of its ions being naturally bound to a location, the Earth's surface, possibly e.g. masts. It is characterised by glowing embers, electron avalanches and negative resistance. It is artificially produced by needle electrodes and requires high voltage. In the case of glowing embers, electron avalanches cause ionisation and also the phenomenon of negative resistance. Negative resistance does not occur at low voltages. At higher voltages (at the ignition voltage), the glow glow is converted into an arc glow under laboratory conditions. In nature, the glow is an uncommon phenomenon that can be captured on high-speed camera images of sharp metal objects, possibly on the tops of masts.
Upwards streamer emanating from the top of a pool cover (https://en.wikipedia.org/wiki/Lightning#cite_ref-57)
GAS DISCHARGE IN CASE OF AIR
At a voltage lower than the ignition voltage of air, the glow of embers, characterised by electron avalanches, appears. At voltages higher than the ignition voltage of air, the electrons are already sufficiently energetic to be capable of thermal emission, which is the characteristic of arc flash. In plasma, also called hot plasma, there may be multiple ionised atoms, and the temperature can increase by leaps and bounds (up to 10 000 K degrees),
https://en.wikipedia.org/wiki/Thermal_ionization).
At a voltage lower than the ignition voltage of air, the glow of embers, characterised by electron avalanches, appears. At voltages higher than the ignition voltage of air, the electrons are already sufficiently energetic to be capable of thermal emission, which is the characteristic of arc flash. In plasma, also called hot plasma, there may be multiple ionised atoms, and the temperature can increase by leaps and bounds (up to 10 000 K degrees),
https://en.wikipedia.org/wiki/Thermal_ionization).
Voltage-current characteristics of electrical discharge (in neon at 1 torr, with two planar electrodes separated by 50 cm).
A: random pulses by cosmic radiation
B: saturation current
C: avalanche Townsend discharge
D: self-sustained Townsend discharge
E: unstable region: corona discharge (when the voltage decreases, the current increases!)
F: sub-normal glow discharge
G: normal glow discharge
H: abnormal glow discharge
I: unstable region: glow-arc transition
J: electric arc (when the voltage decreases, the current increases!)
K: electric arc
B: saturation current
C: avalanche Townsend discharge
D: self-sustained Townsend discharge
E: unstable region: corona discharge (when the voltage decreases, the current increases!)
F: sub-normal glow discharge
G: normal glow discharge
H: abnormal glow discharge
I: unstable region: glow-arc transition
J: electric arc (when the voltage decreases, the current increases!)
K: electric arc
The A-D region is called a dark discharge; there is some ionization, but the current is below 10 microamperes and there is no significant amount of radiation produced.
The F-H region is a region of glow discharge; the plasma emits a faint glow that occupies almost all the volume of the tube; most of the light is emitted by excited neutral atoms.
The I-K region is a region of arc discharge; the plasma is concentrated in a narrow channel along the center of the tube;
a great amount of radiation is produced. (https://en.wikipedia.org/wiki/Electric_discharge_in_gases)
Where a small voltage drop (- Δ U ) is associated with a positive current Δ lg I, (lg denotes a base ten logarithm) there is a "negative resistance" section of the characteristic. The first section with negative resistance is located in the "transition section", where the current does not increase indefinitely, because the formation of high-temperature positive ions is an energy-consuming process.The ignition voltage is preceded by a difficult-to-explain positive resistance section.
In the second negative resistance stage, the increasing current is limited only by conservation laws.The short-term (≈ 10 seconds) stability of ball lightning is explained by the second, negative resistance section.Recombination maintains equilibrium with thermal ionization. The negative (differential or dynamic) resistance is a phenomenon interpreted in plasmas and semiconductors, it occurs at biased loads, i.e. it does not occur at a voltage of U ≈ 0.
In the second negative resistance stage, the increasing current is limited only by conservation laws.The short-term (≈ 10 seconds) stability of ball lightning is explained by the second, negative resistance section.Recombination maintains equilibrium with thermal ionization. The negative (differential or dynamic) resistance is a phenomenon interpreted in plasmas and semiconductors, it occurs at biased loads, i.e. it does not occur at a voltage of U ≈ 0.
The voltage-current relationship of the electric discharge: the self-sustaining discharge is initially characterized by electron avalanches. At a lower voltage, without light emission (transition stage, dark discharge), then a glowing discharge follows, with colliding electron avalanches.Incandescent light has a voltage that decreases with increasing current, a negative resistance, in nature it is an ion channel, which is not yet ball lightning.The process takes place in nature at atmospheric pressure.
DESCRIPTION OF BALL LIGHTNING
Its sources are hard-to-notice ion channels starting from the earth's surface. The ions come from the Earth's surface, the atmospheric tension creates the channels. The channels are not stable phenomena, they are characterized by collisional ionization and gas discharge. The ion channel is characterized by corona discharge, (ember glow, St. Elmo's fire), electron avalanches, and negative resistance (https://en.wikipedia.org/wiki/St._Elmo%27s_fire, cold plasma).
Its sources are hard-to-notice ion channels starting from the earth's surface. The ions come from the Earth's surface, the atmospheric tension creates the channels. The channels are not stable phenomena, they are characterized by collisional ionization and gas discharge. The ion channel is characterized by corona discharge, (ember glow, St. Elmo's fire), electron avalanches, and negative resistance (https://en.wikipedia.org/wiki/St._Elmo%27s_fire, cold plasma).
At a sufficiently high atmospheric voltage, the ion channel turns into arc light, which is similarly characterized by negative resistance but thermal electron emission. In the case of arc light, the channel is separated from the Earth's surface, and a stable phenomenon is created for a few 10 seconds, in accordance with the laws of conservation. Ball lightning is characterized by a high temperature (almost 10,000 degrees Kelvin), inflation, recombination and an ember glow on its surface.Ion channels starting from the Earth or airplanes, or possibly other high-capacity locations, are the source of ball lightning.The connection of the ion channel with the ground and the ion source is broken. The temperature is sufficient for the thermal emission of the electrons of the gas molecules. Inflating spherical shape and negative resistance are characteristic above the ignition voltage, the ions recombine on the surface. This is the stage of the high-temperature arc discharge, the warm plasma state, see the video: https://www.youtube.com/watch?v=1bBNeyrMOJE.
The sphere's size, volume, pressure, and the number of ions are essentially constant, which is possible because almost as many ions are recombined on its surface as are generated inside as a result of thermal emission (equilibrium state). The pressure and volume are approximately constant, but the temperature slowly decreases radially and temporally, due to heat loss. Without an external energy source, it cools by consuming its own energy, the electromagnetic (light, heat) loss is strong, the particles recombine, and the arc sphere collapses under the ignition voltage. Nearly symmetric spheres are the result of the temperature distribution.The radial density distribution of the ions depends on the free path length of the not-yet-ionized oxygen and nitrogen molecules, which flow back from its surface, because otherwise a pressure difference would be created. From the outside, the arc sphere is neutral, from the ionization it follows that the number of electrons and ions is approx. same (https://hu.wikipedia.org/wiki/Debye%E2%80%93H%C3%BCckel-elm%C3%A9let). Approximately, because electrons are cc. five times more mobile, measured by the free path length.
Above the ignition voltage, thermal ionization inside the ball lightning and recombination on its surface are characteristic. Symmetric spheres are the result of heat loss and temperature distribution.The radial density distribution of the ions may show a maximum up to the semi-radius, depending on how far the not yet ionized oxygen and nitrogen molecules penetrate from the outside, from the surface. The recombined air molecules move inside the arch sphere, their movement in the opposite direction would change the atmospheric pressure. Therefore, non-convective energy loss is typical, but rather radiative losses. Due to the poor thermal conductivity of air, the conductive loss is relatively small.
Within the ball lightning, the free path lengths of the electrons and positive ions are decisive, that of the electrons approx. 5.5 times. Collisions reduce the energy of electrons and ions, the energy loss resulting from collisions slows down the movement of particles even in the case of negative resistance. (The movement of ions is also the subject of research in the case of superconductivity - i.e. zero resistance: https://www.popularmechanics.com/science/a62121695/ed
Above the ignition voltage, thermal ionization inside the ball lightning and recombination on its surface are characteristic. Symmetric spheres are the result of heat loss and temperature distribution.The radial density distribution of the ions may show a maximum up to the semi-radius, depending on how far the not yet ionized oxygen and nitrogen molecules penetrate from the outside, from the surface. The recombined air molecules move inside the arch sphere, their movement in the opposite direction would change the atmospheric pressure. Therefore, non-convective energy loss is typical, but rather radiative losses. Due to the poor thermal conductivity of air, the conductive loss is relatively small.
Within the ball lightning, the free path lengths of the electrons and positive ions are decisive, that of the electrons approx. 5.5 times. Collisions reduce the energy of electrons and ions, the energy loss resulting from collisions slows down the movement of particles even in the case of negative resistance. (The movement of ions is also the subject of research in the case of superconductivity - i.e. zero resistance: https://www.popularmechanics.com/science/a62121695/ed
*Literature review: the ball lightning is not a rare phenomenon, many -though sometimes uncertain- observations have been published:
- History of observations Keul, A. G.: A brief history of ball lightning observations by scientists and trained professionals, Hist. Geo Space. Sci., 12, 43-56, https://doi.org/10.5194/hgss-12-43-2021, 2021.
- https://en.wikipedia.org/wiki/Ball_lightning,
- https://hu.wikipedia.org/wiki/G%C3%B6mbvill%C3%A1m,
- https://anyanyelvcsavar.blog.hu/2018/07/20/a_villamok_nepi_osztalyozasa_kulonos_tekintettel_
- https://anyanyelvcsavar.blog.hu/2018/07/20/a_villamok_nepi_osztalyozasa_kulonos_tekintettel_
a_gombvillamra,
- https://www.britannica.com/story/does-ball-lightning-exist.
- https://www.britannica.com/story/does-ball-lightning-exist.
- Corona discharge (https://en.wikipedia.org/wiki/Corona_discharge)
- Nicola Tesla may have produced ball lightning (https://en.wikipedia.org/wiki/Colorado_Springs_Notes,_1899%E2%80%931900) using high-voltage and high-frequency devices.
- At the Max Planc Institute (https://phys.org/news/2006-06-physicists-ball-lightning-lab.html), they produced plasma with a high current arc, but for a very short time compared to the lifetime of ball lightning.
- Researchers in Brazil and New Zealand have experimented with silicon evaporation (https://index.hu/tudomany/villam070112/, http://aparadox.hupont.hu/19/05-brazil-gombvillam). Microwave production experiments have also been carried out (https://www.nature.com/articles/srep28263).
- Nicola Tesla may have produced ball lightning (https://en.wikipedia.org/wiki/Colorado_Springs_Notes,_1899%E2%80%931900) using high-voltage and high-frequency devices.
- At the Max Planc Institute (https://phys.org/news/2006-06-physicists-ball-lightning-lab.html), they produced plasma with a high current arc, but for a very short time compared to the lifetime of ball lightning.
- Researchers in Brazil and New Zealand have experimented with silicon evaporation (https://index.hu/tudomany/villam070112/, http://aparadox.hupont.hu/19/05-brazil-gombvillam). Microwave production experiments have also been carried out (https://www.nature.com/articles/srep28263).
- Kapitza (Kapitza, P. L., Doklady, U.S.S.R. (1955) and https://www.nature.com/articles/185449a0) describes spherical lightning as electromagnetic standing waves, the resonance of a conducting ionized plasma sphere, which occurs when the wavelength of the radiation is about four times the diameter of the fireball. The ionic cohesive field: according to Kapitza (Kapitza, P. L., Doklady, U.S.S.R. (1955) and Silberg, P.A. On the formation of ball lightning. Il Nuovo Cimento C4, 221-235 (1981). https://doi.org/10.1007/BF02507400) the origin of the central cohesive field is an electromagnetic standing wave which on average produces a virtual potential minimum.
- Tibor Neugebauer (Fizikai Szemle, The theory of the fireball / NeugebauerTibor = Vol. 25, 1975, p. 49) describes a quantum theoretical idea based on the exchange interaction, which has not been generally accepted and is difficult to access even in Hungarian.
- There are also a number of ideas that cannot and should not be taken seriously.
- (https://web.archive.org/web/20050224120205/http://www.sulinet.hu/termeszetvilaga/archiv/2000/0015/21.html)
**Observed characteristics (https://en.wikipedia.org/wiki/Ball_lightning):
**Observed characteristics (https://en.wikipedia.org/wiki/Ball_lightning):
- https://www.youtube.com/watch?v=1bBNeyrMOJE,,
- Floating in an erratic orbit, ("mats"), spinning, rolls,
- destroys, though not always,
- often occurs in thunderstorms, but not exclusively and not necessarily thunderstorm related, although more common in thunderstorms,
- can move upwind, speeds of 1-2 m/sec,
- burning holes in partitions, sometimes passing through without a trace.
- Floating in an erratic orbit, ("mats"), spinning, rolls,
- destroys, though not always,
- often occurs in thunderstorms, but not exclusively and not necessarily thunderstorm related, although more common in thunderstorms,
- can move upwind, speeds of 1-2 m/sec,
- burning holes in partitions, sometimes passing through without a trace.
- spherical lightning bolts are described as transparent, opalescent with opaque edges, multicoloured, uniformly luminous, radiating flames, filaments or sparks, varying in shape from spheres, ovals, teardrops and rarely discs,
- disappear suddenly, dissipate gradually, or become engulfed in an object, "popping", exploding loudly, even forcefully, causing serious damage. Reports also vary on their alleged danger to humans, from lethal to harmless. Odours resembling ozone, burning sulphur or nitrogen oxides are often reported.
- They range from 1 to 100 cm in diameter, most often around 10 cm,
- A wide range of colours have been observed, the most common being red, orange and yellow, rarely bluish, usually opalescent.
- Their lifetime lasts from one second to more than a minute, and the brightness remains relatively constant during this time,
- observers rarely report any sensation of heat, but it will burn any object it comes into contact with. In some cases, the disappearance of the sphere has been accompanied by a strong release of heat.
- Some spheres are attracted to metal objects and move along conductors such as wires or metal fences.
- They range from 1 to 100 cm in diameter, most often around 10 cm,
- A wide range of colours have been observed, the most common being red, orange and yellow, rarely bluish, usually opalescent.
- Their lifetime lasts from one second to more than a minute, and the brightness remains relatively constant during this time,
- observers rarely report any sensation of heat, but it will burn any object it comes into contact with. In some cases, the disappearance of the sphere has been accompanied by a strong release of heat.
- Some spheres are attracted to metal objects and move along conductors such as wires or metal fences.
- Some have appeared inside buildings without warning, passing through locked doors and windows, and have also appeared inside metal aircraft, entering and leaving without causing damage.
- Possible spectra: silicon, calcium, iron, nitrogen, oxygen emission lines were observed in a Chinese spectral measurement from a long distance, probably partly pollution.