Ball lightning – the main mystery of atmospheric electricity

Ball lightning looks like a glowing sphere that usually appears during a thunderstorm. Often such an object hangs or moves at a more or less fixed height above the ground. Sometimes ball lightning explodes when it collides with some object or for no apparent reason. It is noteworthy that there is still no universally recognized physical theory explaining the nature of ball lightning.

Electrical phenomena in the Earth’s atmosphere, despite centuries of research, remain poorly understood in many respects. Ball lightnings ─ probably one of the biggest mysteries, starting with the fact of their existence, said Mikhail Leonidovich SHMATOV, doctor of physical and mathematical sciences, senior researcher of solid state theory of A.F. Ioffe Physics and Technology Institute of Russian Academy of Sciences. In the interview the scientist told about the most interesting issues related to ball lightning.

─ Is it true that up to 2012 the scientific community was not firmly convinced that ball lightning really exists and only after the sensational observation of Chinese scientists who discovered iron, silicon and calcium in such lightning did they start talking about ball lightning as a real object? Earlier there were even suggestions that ball lightning ─ is a kind of hallucination caused by the influence of magnetic fields from some common lightning?

─ Nothing fundamentally new happened in 2012, no revolutionary data was presented by the Chinese scientists based on their observations. The question remains open: whether they observed ball lightning? Most likely (and it is mentioned in our joint review with Professor Karl Stefan from the University of Texas at San Marcos) [1], the Chinese scientists saw the consequences of an ordinary lightning strike on a power line. They are sometimes thought to have established the presence of iron, calcium and silicon impurities in the ball lightning. But probably the registration of spectral lines of these elements ─ is simply the result of the impact of the discharge of ordinary lightning on the power line and the ground, perhaps, some effects associated with the fact that this discharge produced a short circuit of the power line also manifested. Let me remind you that all of this was near a power line, so there could have been a ground fault, which led to these consequences.

However, in terms of how people perceive ball lightning, the situation is really complicated. Many people are interested in ball lightning, but there are plasma physicists who know nothing about this object. This is the current situation.

If we talk about hallucinations, it is believed that in some cases people can see some luminous spots because of the action of a very bright flash of light from ordinary lightning. There has also been work to the effect that perhaps the magnetic fields from ordinary lightning act directly on the brain and give optical illusions of a more complex origin.

There are a large number of luminous long-lived objects that can be mistaken for ball lightning. A wonderful example that has been discussed in the scientific literature is that in some cases even a bird living in a hollow tree can be mistaken for ball lightning! The bird can be stained with rotting wood, and rotting wood glows under certain conditions.

I believe that in the case of the mentioned observation of the Chinese scientists, the results of which were published in their article, the situation is about the same: they could see the consequences of a simple lightning strike and not a ball lightning.

Yes, there are still those who still do not know about ball lightning and those who think that it is an optical illusion, but today it is already known for sure: ball lightning exists. And we know it, in particular, from a number of reports about destructive effects caused by such lightning.

Ball lightnings have been known for thousands of years. Why has it not been possible to unambiguously determine their nature so far?

─ I believe that one of the main problems is the lack of sufficiently large-scale and well-funded research in this field.

Important research on ball lightning was done in the United States in the 1960s. They resulted in the excellent book “The Nature of Ball Lightning” by Stanley Singer. This work was done during the Vietnam War, and the maximum task was “to scare the hell out of the Viet Cong,” which can be translated as “scare the hell out of the Viet Cong,” that is, the National Liberation Front of South Vietnam, which I learned about after Singer’s death. But no one is facing such tasks now, and so interest in ball lightning is moderate. In addition, the great complexity and lack of obvious applicability discourage many.

However, I think that the study of ball lightning has important political significance for plasma physics, because there is currently a problem of energy production, and one of the promising solutions, as we know, is controlled thermonuclear fusion.

The position of many researchers in the field of controlled thermonuclear fusion is that if enough money is allocated, humanity will get this source of energy, because the physics of plasma is well understood. But one may ask: why do you think you understand plasma physics at all? Well, we solved one problem, and the other one ─ all right. But there is such a natural phenomenon as ball lightning. It is known for thousands of years, it is associated with plasma, but has not yet been explained definitively. Until we explain ball lightning, we can hardly say that the physics of plasma is well understood.

─ Plasma, as far as I know, is considered to be the most understudied state of matter…

─ It’s a difficult question. I believe that a number of aspects in this area are very well studied. If the physics of plasma had not been well studied, there would have been no hydrogen bombs in particular. Nothing was spared on them. And now they exist and, in general, ensure peaceful coexistence on the planet.

─ Is it possible to create ball lightning in laboratory conditions?

─ I would say that there is no direct answer to this question. And it would be more correct to talk about creating ball lightning not so much in the laboratory as at the test site. Why? It is known that ball lightning ─ is a manifestation of thunderstorm activity of the atmosphere, and, generally speaking, in a thunderstorm cloud in some cases there are gigantic potentials. The difference of potentials between different points of the cloud or between a certain point of the cloud and the ground can be a hundred million volts. Under certain conditions, we can even go into the range of several hundred million volts, and perhaps even up to several billion volts. This is why it is better to do the work under range conditions.

There are many attempts to recreate ball lightning in the laboratory. So far this has not yielded any convincing results. And whether it is possible in principle or not, I can’t say. In the framework of my model it is better to work at the test site. Similar experiments have been done at least twice in the U.S. ─ with an attempt to use lightning initiated by missiles pulling a wire. But, as you know, rocket launching ─ is a serious thing. These experiments took place at special ranges, particularly ─ at a National Guard base. This kind of research ─ is a very expensive and dangerous undertaking, because with a missile, if not launched properly, you can also shoot down an airplane, and in any case, if you do not respect safety precautions, you can get hit by an initiated lightning.

Experiments without rockets using ordinary lightning are also quite possible. There are a large number of reports of ball lightning observation conditions. For example, this environment can be reproduced and waited for normal lightning to strike. It is easy to recreate a ball lightning environment, but I will not elaborate on exactly how this can be done now. High cost and safety issues are also important for non-missile experiments.

─ Our compatriot, Nobel laureate Peter Kapitsa, dealt with questions of ball lightning. He wrote that ball lightning, due to its rarity, can hardly be systematically studied. What do you think about it?

─ And here it is not clear at all how rare this phenomenon is. It is believed that for a person living in the area of the middle belt of the former Soviet Union, the probability of encountering ball lightning in a lifetime is about 5%. That’s not much. But in the United States in 1963 an interesting survey was conducted: NASA employees were asked how often they had seen ball lightning and how often they had observed a close strike of ordinary lightning. The number of both turned out to be comparable, which means that it is very difficult to talk seriously about the probability of generating ball lightning during the discharge of ordinary ─. The fact is that ball lightning has a short detection range. Moreover, during thunderstorms, as a rule, all prudent people sit indoors if possible. At the same time a simple lightning is visible at long distances, as it is large and bright, and the sound from it is strong. It is quite possible that the frequency of generation of ball lightning by natural discharges is comparable to the frequency of ordinary lightning. We may just not see ball lightning.

As for the fact that ball lightning is observed, regardless of the reasons, rarely, I do not consider it a significant obstacle to research, because a huge amount of observational data has been accumulated and published. At the same time, it is certainly not possible to trust all reports.

The number of people who have found themselves at a short distance from an ordinary lightning strike is comparable to the number of people who have ever observed ball lightning. By the way, quite a lot of ball lightnings were seen by pilots. I.M. Imanitov, an outstanding researcher of atmospheric electricity, studied this question very thoroughly. He came to the conclusion that in clouds ball lightning occurs a hundred times more often than at low altitudes.

─ By the way, at what height are ball lightnings usually observed?

─ Ball lightning has one very interesting property ─ that it very often hangs or moves at a fixed height, for example around a meter and a half above the ground. And this is actually a very non-trivial fact, because it is obviously affected by both gravity and the Archimedean force. It turns out that a ball lightning ─ is quite light. And it would seem that if ball lightning is heavier than air, it should fall, but if it is lighter than air it should fly up. But ball lightning at least in some cases has an electric charge, which affects its movement. But this is a separate and very complicated issue, so we will not go into details now. In general, ball lightning has been observed directly on the ground or on the floor, at the mentioned height of a meter and a half, and at a height of several kilometers.

How long does a ball lightning live?

─ Ball lightning lifetime ─ is one of the most well-recorded parameters. The lower limit is a few seconds. Apparently, regional peculiarities of ball lightnings are important, as the results of works written in different countries give slightly different boundaries of lifetime. It is safe to say that ball lightning can definitely live a few seconds. But with the upper limit the question is very complicated. There are, for example, published data on observation of M.T. Dmitriev [3]. He saw a ball lightning for about a minute and a half. Probably, we can say that at low altitudes ball lightning can live at least up to three minutes. There are also reports in the literature that ball lightning has lived for up to 15 minutes. But I know of only one or two reports of this kind.

In addition, there is a very insidious effect, outwardly similar to ball lightning, ─ it is St. Elmo’s lights on a flying electric field concentrator. If we have a strong enough field, and the fields under (and in) thunderclouds can be of the order of kilovolt per centimeter, and there is some object or objects, such as a swarm of beetles, then a glow can appear on these beetles or other objects. Scientists have specifically studied this question. It was found that it is very difficult to distinguish between ball lightning and St. Elmo’s lights from a great distance, even if the concentrator of the electric field is not flying.

─ Have you ever observed ball lightning yourself?

─ No.

─ Would you like to?

─ Not really. The fact is that within my model, if you are completely unlucky, you can get severe radiation damage, including lethal damage, from a distance of, in unique cases, tens of meters. Ball lightning is very dangerous to humans.

A very interesting story which looks almost fantastic but was well-documented and described in the Journal of Engineering Physics in 1981 [5] took place in Khabarovsk where a ball lightning melted 440 kilograms of soil. It looks like a scary tale, but very serious studies of this ground were conducted at the Institute of Nuclear Physics of the Moscow State University and other scientific organizations. In particular, according to attempts to reproduce the slag of approximately the same composition, it became clear that the melting was caused either by radio waves or by hard radiation, i.e. gamma rays, but what exactly ─ no definitive conclusion.

Ball lightning is also a danger to machinery, particularly because of its ability to affect the operation of electrical circuits. Both old literature and relatively modern literature describe stories when ball lightning switched on electric lamps. In principle, it can knock out electronics [6], and for modern aircraft, for example, knocking out electronics ─ is a very bad event. There are reports of military pilots even having to eject because of damage to the aircraft by ball lightning [7], but what the specific mechanisms of damage were, I don’t know.

Is ball lightning always associated with ordinary lightning, or can it occur independently of it?

─ In some cases the birth of ball lightning can be associated with a particular ordinary lightning, but there are also known cases when ordinary lightning did not precede the birth of a ball lightning. There are also reports of observations of ball lightnings in clear weather.

─ Your works are also devoted to radiation danger of ball lightnings. How real is this danger?

─ I am interested in the radiation danger of ball lightning and atmospheric electricity in general. Last year and the year before I published two articles [8, 9] where I explained some parameters of gamma-radiation fluxes which were recorded in Japan in one case [10] and in Armenia in another case [11] within the framework of my ball lightning model.

Since about 1980, the fact of generation of X-rays and gamma rays in thunderstorm clouds has been clearly established. There are both short quite powerful pulses, and long streams of gamma-radiation lasting, for example, seconds or minutes, as well as events that can be interpreted as the generation of a large number of pulses. The question of what is the nature of long pulses is open.

There are reports of observing not only single ball lightnings, but also entire groups of ball lightnings [4]. In Armenia, the observation of visible light that comes from clouds, among other things, is carried out at the Aragats station. In 2019 an article by A. Chilingaryan [11] and colleagues was published about how they saw gamma rays and a group of glowing spots. They offered some explanation as to where the light spots, about 10 pieces, came from. I concede that they may have seen a group of ball lightning [9].

─ Could even groups of ball lightnings really exist?

─ Yes. Such events are rare, but they happen. There are documented accounts of pilots who have seen dozens of fireballs in the clouds in emergency situations, like a forced landing at an airfield through a thunderstorm [4]. Let me repeat that the probability of meeting a fireball in a cloud is about hundred times higher than at our usual heights, i.e. at the ground level and some meters above it [2].

In general, the radiation danger of ball lightning for the first time began to be seriously discussed in 1962. Earlier, in 1886, in the Scientific American (now a magazine and the old issues look like a newspaper) there was a unique publication which described the story of how a family in Venezuela in their house observed a bright light and felt a specific smell (in reports about ball lightning sometimes mentioned smell like the smell of burning black powder or sulfur). People began to pray, thinking that it was the end of the world (an assumption perfectly natural to the 19th century and religious family), but this activity was interrupted by vomiting. Subsequently, people developed blisters on their skin that became ulcers, and their hair began to fall out. What, if not radiation, does this look like? And this fact can hardly be considered a falsification, because it was described before the discovery of natural radioactivity, and before the creation of X-ray sources, and even more so before the creation of powerful sources of ionizing radiation. 90 years later, Eugene Garfield interpreted this case as a possible radiation damage from ball lightning.

Rosalyn Krysik observed another interesting effect: a ball lightning bolt flew up to the glass door, and the glass glowed. It was not a reflection, because the lightning was a bluish color, but the glow ─ yellow. Subsequently, Carl Stephan and his colleagues conducted a series of experiments, and it turned out that such an effect could be caused by the action of ultraviolet or harsher radiation [1].

─ Can ordinary lightning also carry a radiation hazard?

─ Yes. Some amount of ordinary lightning (exactly how much ─ is unknown, about 0.01% to 1%) has been found to generate streams of hard radiation. These streams are quite well visible, oddly enough, from satellites, because the radiation interacts with the air – it is simply absorbed and scattered, scattering leads to a decrease in photon energy. The intensity decreases with increasing distance and in a situation where there is almost no absorption and scattering, simply because the same number of quanta falls on a larger area. But a more significant effect is observed in a sufficiently dense atmosphere ─ it is the scattering and absorption of gamma and X-rays by air. Therefore, it appears that if a thunderstorm is several kilometers high and especially higher, it is easier to see the hard radiation from a satellite than from the ground.

Tell me in the end how to protect yourself when you meet a ball lightning? What can and what must not be done?

─ The same safety rules apply here as for ordinary lightning. For example, many people know not to stand under trees during a thunderstorm ─ a lightning strike in a tree can lead to a discharge from the tree trunk to a person standing nearby. With ball lightning the situation is contradictory. There are different recommendations, but one of them I consider dangerous. The general recommendation with regard to ball lightning is that in terms of danger a ball lightning ─ is a big bad dog: you should not tease it, but you should retreat slowly, and slowly ─ is a matter of principle. Why slowly? In principle, it is correct advice, because a sharp movement can create a small discharge, which will bring the ball lightning closer to the person. But sometimes it is advised not to move at all! Strange advice taking into account that there are a number of reports on radiation hazard of ball lightning corresponding to severe damage up to vomiting in the process of observation and it is very high radiation doses, it is a risk of lethal outcome [1, 6, 12].

To summarize, I would like to say that ball lightning has its own specific difficulties. On the one hand, we do not know how rare or frequent ball lightning ─ this is due to the small radius of detection, ball lightning is indeed rarely observed. But on the other hand, it has been known for thousands of years, and for the last hundred years there has been more and more data about ball lightning, there are many very interesting publications, particularly about the dangers of ball lightning. One of the best books published so far ─ the work of Walter Brand called “Ball Lightning” in German, 1923. It is still quoted to this day. Recently this book in a slightly updated version was published in English, and in our library I read its translation into Russian. I very much advise this work to all who are interested in such natural phenomena as ball lightning.

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