The causes of monstrous lightning are cosmic rays. Lightning and cosmic rays

Lightning is a spark discharge of static electricity accumulated in thunderclouds. Unlike discharges generated at work and in everyday life, electrical charges accumulated in clouds are disproportionately greater. Therefore, the energy of the spark discharge - lightning and the resulting currents is very high and poses a great danger to humans, animals, and buildings. Lightning is accompanied by a sound impulse - thunder. The combination of lightning and thunder is called a thunderstorm.

Storm- This is an exceptionally beautiful natural phenomenon. As a rule, after a thunderstorm the weather improves, the air becomes clear, fresh and clean, saturated with ions formed during lightning discharges. Despite this, it must be remembered that a thunderstorm in certain conditions can pose a great danger to humans. Every person should know the nature of the thunderstorm phenomenon, the rules of behavior during a thunderstorm and methods of protection against lightning. A thunderstorm is a complex atmospheric process and its occurrence is caused by the formation of cumulonimbus clouds. Heavy cloudiness is a consequence of significant atmospheric instability. A thunderstorm is characterized by strong winds, often intense rain and snow, sometimes with hail. Before a thunderstorm, “in an hour or two,” the atmospheric pressure begins to drop quickly, until the wind suddenly increases, and then begins to rise.

Thunderstorms can be divided into local, frontal, night, and in the mountains. Most often a person encounters local or thermal thunderstorms. Water vapor in the updraft warm air It condenses at altitude, releasing a lot of heat, and the rising air currents heat up. Compared to the surrounding air, the rising air is warmer, it increases in volume until it turns into a thundercloud. Large thunderclouds contain ice crystals and water droplets. As a result of their fragmentation and friction with each other and with the air, positive and negative charges are formed, under the influence of which a strong electrostatic field arises (the electrostatic field strength can reach 100,000 V/m). And the potential difference between in separate parts clouds, clouds or cloud and earth reaches enormous quantities. When the critical electrical intensity in the air is reached, an avalanche-like ionization of the air occurs - a lightning spark discharge.

A frontal thunderstorm occurs when a mass of cold air moves into an area where warm weather prevails. Cold air displaces warm air, with the latter rising to a height of 5-7 km. Warm layers of air invade into vortices of various directions, a squall is formed, strong friction between the layers of air, which contributes to the accumulation of electrical charges. The length of a frontal thunderstorm can reach 100 km. Unlike local thunderstorms, it usually gets colder after frontal thunderstorms. Night thunderstorms are associated with the cooling of the ground at night and the formation of eddy currents of descending air.

Thunderstorm in the mountains is explained by the difference in solar radiation, to which the southern and northern slopes of the mountains are exposed. Night and mountain thunderstorms are persistent and short-lived. Thunderstorm activity varies in different areas of our planet. World centers of thunderstorms: Java island - 220 thunderstorm hoarfrost per year; Equatorial Africa - 150; Southern Mexico - 142; Panama 132; Central Brazil - 106. Russia: Murmansk - 5; Arkhangelsk - 10; St. Petersburg - 15; Moscow - 20. As a rule, the further south “for the northern hemisphere of the Earth” and the further north “for the southern hemisphere of the Earth”, the higher the thunderstorm activity. Thunderstorms are very rare in the Arctic and Antarctic. There are 16 million thunderstorms on Earth every year. For every m2 of earth's surface there are 2-3 lightning strikes per year. The ground is most often struck by lightning from negatively charged clouds.

Lightning is distinguished by type: linear, pearl and ball. Pearl and ball lightning are quite rare occurrences. Their characteristics: a common linear lightning, which any person encounters many times, has the appearance of a branching line. The current strength in the linear lightning channel is on average 60 - 170 kA; lightning with a current of 290 kA has been recorded. The average lightning has an energy of 0 kW/hour “900 MJ”. The discharge develops in a few thousandths of a second; at such high currents, the air in the lightning channel zone almost instantly heats up to a temperature of 30,000 - 33,000°C. As a result, pressure is sharply applied, the air expands and a shock wave appears, accompanied by a sound impulse - thunder. *Pearl lightning is a very rare and beautiful phenomenon. Appears immediately after linear lightning and disappears gradually. Most often, the discharge of pearl lightning follows the path of the repaired one. The lightning appears to be 12 m apart and resembles pearls strung on a string. Pearl Lightning can be accompanied by exceptional sound effects.

Ball lightning is also quite rare. For thousands of ordinary linear lightning, there are 2-3 ball lightning. Ball lightning, as a rule, appears more often towards the end of a thunderstorm, less often after a thunderstorm. It can have the shape of a ball, ellipsoid, pear, disk, or even a chain of balls. The color of Lightning is red, yellow, orange-red. Sometimes lightning is dazzling white with very sharp outlines. Color is determined by the content of various substances in the air. The shape and color of lightning may change during a discharge. Measure the parameters of ball lightning and simulate it in laboratory conditions failed. Apparently, many observed unidentified flying objects "UFOs" are similar or similar in nature to ball lightning.

Hazardous factors of lightning: Linear lightning. Due to the fact that lightning is characterized by large values ​​of currents, voltages and discharge temperatures, its impact on a person, as a rule, leads to their death. On average, about 3,000 people die from lightning strikes in the world every year, and there are known cases of several people being struck at the same time. A lightning discharge follows the path of least electrical resistance: if you place two masts next to each other - a metal one and a tall wooden one, then lightning will most likely strike the metal mast, although it is lower, because the electrical conductivity of the metal is higher; lightning also strikes clayey and wet areas much more often than dry and sandy ones, since the former have greater electrical conductivity; in the forest, lightning also acts selectively, hitting, first of all, deciduous trees such as oak, poplar, willow, and ash, since they contain a lot of starch. Coniferous trees - spruce, fir, larch and deciduous trees such as linden, walnut, beech - contain a lot of oils, therefore they have high electrical resistance, and lightning strikes them less often.

Out of 100 trees, lightning strikes: 27 percent of poplars; 20 percent pears; 12 percent limes; 8 percent spruce and only 0.5 percent cedar. In addition to damaging people and animals, linear lightning quite often causes forest fires, as well as residential and industrial buildings, especially in rural areas. In this regard, it is necessary to take special protection against linear lightning. Ball lightning. If the nature of linear lightning is clear, and, therefore, its behavior is predictable, then the nature of ball lightning is still not clear. The danger of a person being struck by ball lightning is, first of all, associated precisely with the lack of methods and rules for protecting people from it.

In 1753, Russian physicist Georg Wilhelm Richmann, colleague of M.V. Lomonosov, was killed by ball lightning during a thunderstorm while researching spark discharges in the atmosphere. There are many known cases of people dying when encountering ball lightning. A dramatic incident occurred with a group of five Soviet climbers on August 17, 1978 in the Caucasus at an altitude of about 4000m, where they stopped for the night on a clear, cold night. A light yellow ball the size of a tennis ball flew into the climbers’ tent. The ball hovered over the sleeping bags in which the climbers were located, and methodically, according to some plan of its own, penetrated into the sleeping bags. Each such “visit” caused a desperate inhuman cry, people felt extreme pain, as if they were being burned with an autogenous gas, and lost consciousness. They could not move their arms or legs. After the ball “visited” the sleeping bags of each climber several times, it disappeared. All climbers received many serious wounds. These were not burns, but lacerations: the muscles were torn out in whole pieces, right down to the bones. One of the climbers, Oleg Korovin, was killed by the ball. At the same time, the ball lightning did not touch a single object in the tent, but only injured people.

The behavior of ball lightning is unpredictable. She suddenly appears anywhere, including indoors. Cases of ball lightning appearing from a telephone handset, an electric razor, a switch, a socket, or a loudspeaker have been observed. It quite often enters buildings through pipes, open windows and doors. Ball lightning sizes range from several centimeters to several meters. Usually it easily floats or rolls above the ground, sometimes jumps. It reacts to wind, draft, rising and moving air currents. However, there was a case when ball lightning did not react to the air flow.

Ball lightning can appear without causing harm to a person or premises, fly through a window and disappear from the premises through open door or a chimney, flying past a person. Any contact with it leads to severe injuries, burns, and in most cases, death. Wide lightning may explode. The resulting air wave can injure a person or lead to destruction in a building. There are known cases of lightning explosions in stoves and chimneys, which led to the destruction of the latter. The collected evidence on the behavior of ball myopia suggests that in most cases the explosions were not dangerous, severe consequences occurred in 10 cases out of 100. It is believed that ball lightning has a temperature of about 5000 ° C and can cause a fire.

`Rules of behavior during a thunderstorm:

We see a flash of lightning almost instantly, as light travels at a speed of 300,000 km/s. The speed of sound in air is approximately 344 m/s, that is, in about 3 seconds, sound travels 1 km. Lightning is dangerous when the flash is immediately followed by a clap of thunder, which means that a thundercloud is above you, and the danger of a lightning strike is most likely. Your actions before and during a thunderstorm should be winter-proof: leave the house, close windows, doors and chimneys, make sure that there is no draft that can attract ball lightning. During a thunderstorm, do not light the stove, since the smoke coming out of the chimney has high electrical conductivity, and the likelihood of a lightning strike into the chimney rising above the roof increases; During a thunderstorm, stay away from electrical wiring, antennas, windows, doors and everything else connected to the external environment. Do not sit near a wall next to which there is a tall tree; disconnect radios and televisions from the network, do not use electrical appliances and telephones “this is especially important for rural areas”; “and it’s time to walk and hide in the nearest building. A thunderstorm in a field is especially dangerous. When looking for shelter, give preference to a metal structure large sizes or a structure with a metal frame, a residential building or a fugue building protected by a lightning rod; if it is not possible to hide in a building, there is no need to hide in small sheds or under lonely trees; do not stay on hills and open unprotected places, near metal or mesh fences, large metal objects, wet walls, lightning rod grounding; in the absence of shelter, lie on the ground, and preference should be given to dry sandy soil, far from the reservoir; If a thunderstorm finds you in the forest, you need to rummage through an area with low-growing trees. You cannot take shelter under tall trees, especially pine trees, oaks, and poplars. It is better to be no more than 30 m away from a separate tall tree. Pay attention to whether there are any nearby trees that were previously damaged by a thunderstorm and split. It's better to stay away from this place. The abundance of trees struck by lightning indicates that the soil in this area has high electrical conductivity, and a lightning strike in a muddy area is very likely. During a thunderstorm, you cannot be on the water and you cannot swim or fish near the water. It is necessary to move further away from the beret, and in the mountains, move away from the mountain ridges of sharp towering skips and peaks. When a thunderstorm approaches in the mountains, you need to go as low as possible. Collect metal objects - climbing pitons, ice axes, pots - into a backpack and lower them on a rope 20-30 m down the slope; during a thunderstorm, do not engage in outdoor sports or run, as it is believed that sweat and rapid movement “attract” lightning; if you are caught in a thunderstorm on a bicycle or motorcycle, stop driving, leave them and wait out the thunderstorm at a distance of about 30 m from them; If a thunderstorm finds you in your car, you do not need to leave it. It is necessary to close the windows and lower the car antenna. It is not recommended to drive a car during a thunderstorm, since a thunderstorm is usually accompanied by rain, which impairs visibility on the road, and a flash of lightning can blind and cause fear and, as a result, an accident; When encountering ball lightning, do not show any activity towards it, if possible, remain calm and do not move. There is no need to approach her or touch her with anything, because... an explosion may occur. You should not run away from ball lightning, because this can cause it to flow with the resulting air flow.

Lightning protection:

An effective means of protection against lightning is lightning rods. The priority of the invention of the lightning rod belongs to the American Benjamin Franklin “1749”. Somewhat later, in 1758, independently of him, the lightning rod was invented by M.V. Lomonosov. Lightning protection by installing lightning rods is based on the property of lightning to strike the highest and well-grounded metal structures. The lightning rod consists of three main parts: an air terminal that receives a lightning strike; a current conductor connecting the lightning rod to the ground electrode, through which the lightning current flows into the ground. The most common types of air terminals are rod and cable. Lightning rods are divided into: single, double and multiple.

A protection zone is formed around the lightning rod, that is, a space within which the structure or any other object is protected from direct blow lightning. The degree of protection in these areas is more than 95 percent. This means that out of 100 lightning strikes, less than 5 hits are possible on a protected object; the remaining strikes will be perceived by the lightning rod. The protection zone is limited by the generatrices of two cones, one of which has a height h equal to the height of the lightning rod and a base radius R = 0.75 h, and the other has a height of 0.8 h and a base radius of 1.5 h “with the base radius of the second cone R = h protection efficiency is ensured at 99 percent.”

Lightning rod lightning rods are made of steel of any profile, usually round, with a cross-section of at least 100 mm2 and a length of at least 200 mm. To protect against corrosion, they are painted. Lightning rods of cable lightning rods are made of metal cables with a diameter of about 7 mm. Current conductors must withstand the heat of very high lightning currents flowing over a short period of time, so they are made from metals with low resistance. The cross-section of current conductors in the air should not be less than 48 mm2, and in the ground - 160 mm2. Grounding conductors are the most important element of lightning protection. Their purpose is to provide a sufficiently low resistance to the spread of lightning current in the ground. As a grounding conductor, you can use metal pipes, slabs, coils of wire and mesh, pieces of predatory reinforcement buried in the ground to a depth of 2 - 2.5 m. It is advisable to install lightning rods on hills to shorten the lightning path and increase the size of the protection zone. Chimneys, gables , roof ledges, television antennas must be grounded using current conductors. drainpipes and stairs leading to the roof should preferably be connected to a current conductor or grounded separately.

Lightning is a spark discharge of static electricity accumulated in thunderclouds. Unlike the charges generated at work and in everyday life, the electrical charges accumulated in the clouds are disproportionately greater. therefore, the energy of the spark discharge - lightning and the currents resulting from this are very high and pose a great danger to humans, animals, and buildings. lightning is accompanied by a sound impulse - thunder. The combination of lightning and thunder is called a thunderstorm.

A thunderstorm is an exceptionally beautiful natural phenomenon. As a rule, after a thunderstorm the weather improves, the air becomes transparent, fresh and clean, saturated with ions formed during lightning discharges.
Despite this, it must be remembered that a thunderstorm in certain conditions can pose a great danger to humans. Every person should know the nature of the thunderstorm phenomenon, the rules of conduct during a thunderstorm and methods of protection against lightning.

Thunderstorm is a complex atmospheric process, and its occurrence is caused by the formation of cumulonimbus clouds. heavy cloudiness is a consequence of significant atmospheric instability. A thunderstorm is characterized by strong winds, often intense rain (snow), sometimes with hail. before a thunderstorm (an hour or two before a thunderstorm), the atmospheric pressure begins to drop quickly until the wind suddenly increases, and then begins to rise.

Thunderstorms can be divided into local, frontal, night, and in the mountains. most often a person encounters local or thermal thunderstorms. These thunderstorms occur only in hot weather with high atmospheric humidity. As a rule, they occur in the summer at midday or afternoon (12-16 hours). water vapor in the rising flow of warm air condenses at altitude, releasing a lot of heat and heating the rising air flows. Compared to the surrounding air, the rising air is warmer and increases in volume until it becomes a thundercloud. Ice crystals and water droplets constantly hover in large thunderclouds. as a result of their fragmentation and friction with each other and with the air, positive and negative charges are formed, under the influence of which a strong electrostatic field arises (the electrostatic field strength can reach 100,000 V/m). and the potential difference between individual parts of the cloud, clouds or cloud and earth reaches enormous values. When the critical intensity of the electric air is reached, an avalanche-like ionization of the air occurs - a lightning spark discharge.

A frontal thunderstorm occurs when a mass of cold air moves into an area where warm weather prevails. cold air displaces warm air, with the latter rising to a height of 5-7 km. warm layers of air invade into vortices of various directions, a squall is formed, strong friction between layers of air, which contributes to the accumulation of electrical charges. The length of a frontal thunderstorm can reach 100 km. Unlike local thunderstorms, it usually gets colder after frontal thunderstorms.
a night thunderstorm is associated with the cooling of the ground at night and the formation of eddy currents of rising air.
thunderstorms in the mountains are explained by the difference in solar radiation to which the southern and northern slopes of the mountains are exposed. night and mountain thunderstorms are weak and short-lived.

Thunderstorm activity varies in different areas of our planet. world centers of thunderstorms: Java island - 220, equatorial Africa - 150, southern Mexico - 142, Panama - 132, central Brazil - 106 thunderstorm days per year. Russia: Murmansk - 5, Arkhangelsk - 10, St. Petersburg - 15, Moscow - 20 thunderstorm days a year.

As a rule, the further south you go (for the northern hemisphere of the Earth) and the further north (for the southern hemisphere of the Earth), the higher the thunderstorm activity. Thunderstorms are very rare in the Arctic and Antarctic. 16 million thunderstorms occur on Earth per year. For every square kilometer of the Earth's surface there are 2-3 lightning strikes per year. The ground is most often struck by lightning from negatively charged clouds.
According to the type of lightning, lightning is distinguished into linear, pearl and ball. Pearl and ball lightning are quite rare occurrences.

Common linear lightning, which any person encounters many times, looks like a branching line. The current strength in the linear lightning channel is on average 60 - 170 kA; lightning with a current of 290 kA has been recorded. The average lightning carries energy of 250 kW/hour (900 MJ). energy is mainly realized in the form of light, heat and sound energies.

The discharge develops in a few thousandths of a second; at such high currents, the air in the zone of the lightning channel almost instantly heats up to a temperature of 30,000-33,000 ° C. As a result, the pressure rises sharply, the air expands - a shock wave appears, accompanied by a sound pulse - thunder.

Before and during a thunderstorm, occasionally in the dark on the tops of tall pointed objects (tops of trees, masts, tops of sharp rocks in the mountains, crosses of churches, lightning rods, sometimes in the mountains on people’s heads, raised hands or animals) one can observe a glow that has received name "St. Elmo's Fire". this name was given in ancient times by sailors who observed the glow at the tops of the masts of sailing ships.

The glow occurs due to the fact that on tall pointed objects the intensity of the electric field created by static electric charge clouds, especially high; as a result, ionization of the air begins, a glow discharge occurs and reddish tongues of glow appear, at times shortening and lengthening again. You should not try to extinguish these fires, because there is no combustion. at high electric field strength, a bunch of luminous filaments may appear - a corona discharge, which is accompanied by hissing. Linear lightning can also occasionally occur in the absence of thunderclouds. It is no coincidence that the saying arose - “thunderbolt among clear skies».

pearl zipper a very rare and beautiful phenomenon. appears immediately after the linear lightning and disappears gradually. Predominantly, a pearl lightning discharge follows a linear path. lightning has the form of luminous balls located at a distance of 7-12 m from each other, resembling pearls strung on a thread. Pearl lightning may be accompanied by significant sound effects.

ball lightning also quite rare. per thousand ordinary linear lightning there are 2-3 ball lightning. ball lightning, as a rule, appears during a thunderstorm, more often towards its end, less often after a thunderstorm. occurs, but very rarely, in the complete absence of thunderstorm phenomena. can have the shape of a ball, ellipsoid, pear, disk, or even a chain of connected balls. the color of the lightning is red, yellow, orange-red, surrounded by a luminous veil. sometimes lightning is dazzling white with very sharp outlines. color is determined by the content of various substances in the air. The shape and color of lightning may change during a discharge. It was not possible to measure the parameters of ball lightning and simulate it in laboratory conditions. Apparently, many observed unidentified flying objects (UFOs) are similar or similar in nature to ball lightning. You can read more about the nature of ball lightning

The nature of lightning was unraveled back in 1749 by the American naturalist Benjamin Franklin, who established that lightning is electrical discharges between a thundercloud and the ground. Until now, scientists believed that when negative charges accumulate in a cloud, an electric field arises between it and the surface, and when it reaches a certain threshold energy, a “breakdown” occurs and an electrical discharge occurs - lightning.

“Everything would be great, but the calculated value of the threshold field is ten times higher than the actually observed value of the electric field at which lightning occurs,” said one of the members of Gurevich’s research group, Corresponding Member of the Russian Academy of Sciences Kirill Zybin. “We need some kind of seed for lightning; apparently, seed particles of sufficiently high energies are required. natural conditions such natural particles are cosmic rays,” the agency’s interlocutor said.

He and his colleagues found that the occurrence of lightning is associated with a phenomenon called “runaway electron breakdown” - an avalanche-like multiplication in matter of fast electrons with an energy of 0.1-10 megaelectronvolts, the cause of which, in turn, is the action of cosmic radiation. Streams of high-energy particles penetrating into the atmosphere supply “seed electrons,” which provoke breakdown at fields ten times lower than required by the previous theory.

“Of course, it is impossible to say that lightning is a breakdown on runaway electrons. But they are connected. In ordinary discharges, such high energies could not appear in gamma rays,” Zybin said. According to him, experimental verification theory causes great difficulties: under normal atmospheric conditions, the length of the “avalanche” that occurs during a breakdown reaches 50 meters.

“In this case, you need to build huge machines, apply very large fields. But such conditions are naturally realized in a thunderstorm atmosphere,” he said. Another effect associated with lightning is gamma-ray flashes. Lightning does not move evenly, but in jumps - “steps”. Scientists have discovered that at each “step” gamma quanta with an energy of tens of megaelectronvolts are emitted.

According to Zybin, at the high-mountain station of the Lebedev Physical Institute in the Tien Shan, experiments are being conducted to study lightning in " natural environment". "Counters are placed there and gamma radiation is measured, and the readings occur at very short intervals. We can say unequivocally that in the absence of a thunderstorm there are no signals, but when a thunderstorm begins, strong flashes and gamma-ray bursts begin, they correlate with radio pulses that are caused by thunderstorm processes,” the scientist said.

He noted that studying the mechanisms of lightning formation will make it possible to understand those discovered in Lately phenomena, in particular, giant high-altitude discharges between thunderclouds and the ionosphere (“sprite”).

According to FIAN scientists, these studies provide new opportunities both in the analysis of climate change and in the mechanisms of influence on the atmosphere.

Every second, approximately 700 lightning, and every year about 3000 people die due to lightning strikes. The physical nature of lightning has not been fully explained, and most people have only a rough idea of ​​what it is. Some discharges collide in the clouds, or something like that. Today we turned to our physics writers to learn more about the nature of lightning. How lightning appears, where lightning strikes, and why thunder thunders. After reading the article, you will know the answer to these and many other questions.

What is lightning

Lightning– spark electric discharge in the atmosphere.

Electric discharge is the process of current flow in a medium associated with a significant increase in its electrical conductivity relative to the normal state. Exist different types electrical discharges in gas: spark, arc, smoldering.

A spark discharge occurs at atmospheric pressure and is accompanied by a characteristic spark crack. A spark discharge is a set of filamentary spark channels that disappear and replace each other. Spark channels are also called streamers. The spark channels are filled with ionized gas, that is, plasma. Lightning is a giant spark, and thunder is a very loud crack. But it's not that simple.

Physical nature of lightning

How is the origin of lightning explained? System cloud-ground or cloud-cloud It is a kind of capacitor. The air plays the role of a dielectric between the clouds. The bottom of the cloud has negative charge. When there is a sufficient potential difference between the cloud and the ground, conditions arise in which lightning occurs in nature.

Step Leader

Before the main flash of lightning, a small spot can be observed moving from the cloud to the ground. This is the so-called stepped leader. Electrons, under the influence of a potential difference, begin to move towards the ground. As they move, they collide with air molecules, ionizing them. A kind of ionized channel is laid from the cloud to the ground. Due to the ionization of air by free electrons, the electrical conductivity in the leader’s trajectory zone increases significantly. The leader, as it were, paves the way for the main discharge, moving from one electrode (cloud) to another (ground). Ionization occurs unevenly, so the leader can branch.

Backfire

The moment the leader approaches the ground, the tension at his end increases. A response streamer (channel) is thrown out from the ground or from objects protruding above the surface (trees, roofs of buildings) towards the leader. This property of lightning is used to protect against it by installing a lightning rod. Why does lightning strike a person or a tree? In fact, she doesn't care where to hit. After all, lightning seeks the shortest path between earth and sky. This is why it is dangerous to be on the plain or on the surface of the water during a thunderstorm.

When the leader reaches the ground, current begins to flow through the laid channel. It is at this moment that the main lightning flash is observed, accompanied by a sharp increase in current strength and energy release. The relevant question here is, where does the lightning come from? It is interesting that the leader spreads from the cloud to the ground, but the opposite bright flash, which we are used to seeing, spreads from the ground to the cloud. It is more correct to say that lightning does not come from heaven to earth, but occurs between them.

Why does lightning thunder?

Thunder results from a shock wave generated by the rapid expansion of ionized channels. Why do we first see lightning and then hear thunder? It's all about the difference between the speeds of sound (340.29 m/s) and light (299,792,458 m/s). By counting the seconds between thunder and lightning and multiplying them by the speed of sound, you can find out at what distance from you the lightning struck.

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Types of lightning and facts about lightning

Lightning between sky and earth is not the most common lightning. Most often, lightning occurs between clouds and does not pose a threat. In addition to ground-based and intra-cloud lightning, there are lightning that forms in upper layers atmosphere. What types of lightning are there in nature?

• Intracloud lightning;
• Ball lightning;
• "Elves";
• Jets;
• Sprites.

The last three types of lightning cannot be observed without special instruments, since they are formed at an altitude of 40 kilometers and above.

Here are some facts about lightning:

• The length of the longest recorded lightning on Earth was 321 km. This lightning was spotted in Oklahoma 2007.
• The longest lightning lasted 7,74 seconds and was recorded in the Alps.
• Lightning is formed not only on Earth. We know for sure about lightning on Venus, Jupiter, Saturn And Uranus. Saturn's lightning is millions of times more powerful than Earth's.
• The current strength in lightning can reach hundreds of thousands of amperes, and the voltage can reach billions of volts.
• The temperature of the lightning channel can reach 30000 degrees Celsius is in 6 times the surface temperature of the Sun.

Ball lightning

Ball lightning is a separate type of lightning, the nature of which remains a mystery. Such lightning is a luminous object in the shape of a ball moving in the air. According to limited evidence, ball lightning can move along an unpredictable trajectory, split into smaller bolts, explode, or simply disappear unexpectedly. There are many hypotheses about the origin of ball lightning, but none can be considered reliable. Fact - no one knows how ball lightning appears. Some hypotheses reduce the observation of this phenomenon to hallucinations. Ball lightning has never been observed under laboratory conditions. All scientists can be content with is eyewitness accounts.

Finally, we invite you to watch the video and remind you: if a coursework or test falls on your head like lightning on a sunny day, there is no need to despair. Student service specialists have been helping students since 2000. Seek qualified help at any time. 24 hours a day, 7 days a week we are ready to help you.

In 1992, Russian physicist Alexander Gurevich from the Physical Institute. P. N. Lebedev RAS suggested that lightning is caused by cosmic rays that enter the Earth's atmosphere.

No, of course, we have all heard about Benjamin Franklin's hypothesis, according to which lightning is a discharge that occurs between clouds and the surface of the Earth simply due to the difference in their charges. There is, however, a rather weak point in this concept. For a discharge to occur, it is necessary that there be too great a charge difference between the clouds and the surface (or neighboring clouds). As it turned out from information obtained by weather balloons in the 1990s, in practice no more than one tenth of this difference is observed. However, lightning still seems to happen. So due to what?

Alexander Gurevich and Co. believe that high-energy particles in the atmosphere trigger a process called runaway electron breakdown (RUE). And the “trigger” of the PUE is cosmic rays. These streams of charged particles, mainly protons, generated by distant supernova explosions (and other processes), entering the atmosphere and colliding with the nuclei of air atoms, cause an avalanche-like process of the formation of free electrons with significant energy (widespread air showers).

Electric fields in thunderclouds accelerate electrons to near-light speeds. Further collisions of electrons with air atoms give rise to additional free electrons, as well as X-ray and gamma radiation (“dark lightning”, which KL never tires of writing about), which transform into filaments of electrical discharges - streamers, well-conducting channels, the merging of which creates thermally ionized channel with high conductivity (also known as a stepped lightning leader).

In theory, everything looks very harmonious: PUE appears in the atmosphere in a constant electric field, an order of magnitude smaller than the field of a conventional breakdown, that is, in the presence of cosmic rays, the observed atmospheric electric fields are finally sufficient to explain the phenomenon of both dark lightning and its visible analogue .

But until very recently, all this remained only a theory: there was no concrete evidence that it was cosmic rays that were responsible for the onset of runaway electron breakdown.

Alas, it turned out to be quite difficult to reproduce such processes in the laboratory, and the point is not only that this requires a voltage of 10 million volts. It has long been known that cosmic rays, entering earth's atmosphere, generate radio pulses, and during thunderstorms there are more radio pulses with similar parameters than when there are no thunderstorms.

To check the hypothesis against observations, Alexander Gurevich and Anatoly Karashtin from the Radiophysical Research Institute (Nizhny Novgorod) analyzed data from radio interferometers taken from 3,800 lightning strikes over Russia and Kazakhstan. Because radio interferometers can link the radio waves they record to specific directions, scientists have been able to unambiguously correlate hundreds and even thousands of short, strong radio pulses with the moments immediately preceding lightning strikes. Moreover, it turned out that the specific parameters of radio pulses coincide with the theoretically predicted features of their generation by cosmic rays.

So, it turns out that the observations explained everything? In fact, although it has been confirmed that cosmic rays play the role of a “seed” for dark lightning and accompanying ordinary lightning, an important ambiguity remains. Over Russia and Kazakhstan there simply are not enough cosmic rays of the necessary energies to generate the observed “collapse” of lightning.

To explain this “discrepancy,” physicists analyzed the nature of the possible interaction of waves recorded by radio interferometers with drops of water and hailstones (hydrometeors). It turned out that when low-energy electrons accompanying free high-energy electrons pass by drops and hailstones in the atmosphere, a series of microdischarges are triggered, radically enhancing both the electric field in the area where the future lightning occurs and the radio pulse, which was later recorded by instruments.

Top: Rate of cosmic rays hitting the Earth's atmosphere. Bottom: Frequency of lightning strikes per unit area. It is clearly seen that cosmic rays alone are not enough to generate lightning: they need interaction with water droplets.