Tunguska meteorite and his younger brothers

... Suddenly, in the north, the sky split in two, and there was a fire wide and high above the forest that swept the entire northern part of the sky. At that moment I felt so hot, as if my shirt was on fire. I wanted to tear off and throw off my shirt, but the sky slammed and there was a strong blow. I was thrown off the porch by three. After the blow, there was such a knock, as if stones were falling from the sky or shooting from cannons, the earth was trembling, and when I was lying on the ground, I pressed my head, fearing that the stones would not break through my head. At that moment, when the sky opened, a hot wind swept from the north, as if from a cannon, which left tracks on the ground in the form of paths. Then it turned out that many of the windows in the windows were broken, while the barn broke the iron tab for the door lock ...

Thus began the morning of July 17 (old style) in 1908 for residents of the Vanavara trading station in the Podkamennaya Tunguska area. The second sun flashed in the sky, which in the next moment became a thousand suns! The flash of light blinded and burned with heat, and the next moment a terrible explosion of unprecedented strength shook the taiga, dumping the forest on a huge area, raising the Evenks into the air. The Evenks lost a lot of deer - one died of the explosion and burned in the fire, others scattered in the taiga in horror and probably died too. And the blast wave flew further and doubled around the globe, marking on the atmospheric pressure records of many meteorological stations around the world. And in front of her another wave rushed - seismic. The Earth’s magnetic field also shuddered, and the microscopic dust formed in the upper atmosphere turned several nights into “white nights”, illuminated by extraordinary bright red dawns, by the light of which in London you could freely read the newspaper. And after them came the brightest noctilucent clouds.

Kulik trail

Nowadays, if you notice the flight of a more or less large bolide that could have reached the earth, the search for a fallen meteorite will be organized almost immediately. At the same time they talked about the car and the phenomena caused by it, made some noise and ... forgot.
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In 1912, in one of the expeditions in the Urals, Academician V.I. Vernadsky attracted to the work of a local resident, assistant forester, exile Leonid Alekseevich Kulik. Seeing his perspective, Vernadsky obtained permission for him to study in St. Petersburg. And in 1913, Kulik, already a student of St. Petersburg University, became an employee of the Mineralogical Museum of the Academy.

One of the tasks of Kulik was the registration and systematization of information about the fall of meteorites, which were received by the Academy of Sciences. At that time, she was experiencing hard times and organizing an expedition to search for them could only dream of. This dream was destined to be fulfilled only after the revolution — in 1921, at the initiative of Vernadsky, a meteorite department was established at the Academy of Sciences, and Kulik managed to do the incredible thing - get through to Lunacharsky, interest him and convince him of the need to allocate funds to organize an expedition to replenish the meteorite collection and verification of the information that was previously received. From the funds of the People's Commissariat of Education, Kulik received several million - still full-fledged, and not those that they became a little later:

A dream come true, I became a millionaire
I know a myriad of zeros ...

And besides these millions - special wagon, equipment and food.

Everyone knows the jokes about flying in a pack of "Belomor". The first expedition of Kulik went on ... a leaf of the tear-off calendar. In this leaflet there was a message that the passengers of the train passing through the Filimonovo junction near Kansk, saw the fall of a giant meteorite, the explosion of which frightened the driver, forcing the train to stop. It was impossible to pass by this, so this crossing became one of the key points of the Kulik expedition. On-site it turned out that the car was indeed observed, but it fell somewhere far to the north. In search of the place of the fall, Kulik traveled all over the Yenisei province, collecting eyewitness reports that they had seen and heard and mapped the directions indicated by them. They converged far to the north, in the Podkamennaya Tunguska area.

Meanwhile, the time and resources allocated for the expedition ended, and the special wagon needed to be returned to the people's commissariat of communications. In May 1922, the expedition returned, having made a journey of twenty thousand kilometers and with a “catch” in the form of a dozen meteorites to the collection of the Academy of Sciences. And the data collected by Kulik, added information about a strange earthquake, the epicenter of which was located in the upper Podkamennaya Tunguska, and the focus was not deep in the bowels of the Earth, but directly on the surface, followed by the arrival of an air wave recorded on a barograph tape. And after them, scientists came up with rumors of an unprecedented explosion that shook the Evenks in the same lands, about a gigantic 700-kilometer fall of the forest.

The new expedition could not be organized - there was no money, none of the officials at this time took its tasks seriously. It was only in 1926, in February, that it nevertheless took place - there were only two people in its composition - Kulik and his assistant Alexander Emilevich Gulich, with whom he served in the army even before the First World War. This time they had neither a personal carriage, nor mandates for assistance, and they literally got their way. To Taishet by train, and then the only means of transport were horses. So we got to Vanavara.
Now from the cherished place they were separated by 80 kilometers of virgin snow and ... again the opposition - this time the Evenks. They did not like the strange Russian who was striving for a bewitched place. Even when one of the Evenks agreed to be a guide, he tried his best to slow down the path, which took two weeks instead of a couple of days. And finally, Kulik and Gulich saw the whole picture of destruction.

It was very dangerous to walk here, especially in the first half of the day, when there was windy weather. At that time, twenty-meter dead giants, rotting at the roots, fell to the ground with a crash. It was necessary to keep an eye on the dead naked peaks, in time to have time to bounce to the side, and at the same time not forget to look at your feet, since the terrain was swarming with poisonous snakes

So Kulik describes the epicenter of the catastrophe, where dead trees stood with torn off branches and trunks burnt along the entire length. And around the trees were laid along the radius - tops from the center of the basin. And right there, in the hollow, there were many craters. Kulik had no doubt that this is the place where the meteorite fell. But there was no time left for his search - food was running out, it was necessary to return to Vanavara, and then to Leningrad.

Kulik was sure that he was two steps away from the discovery. But scientists of the Academy of Sciences did not share his confidence. The funnels seemed to them familiar and unrelated to any meteorites - such are formed during the melting of permafrost. And the forest could burn without any meteorite. Maybe there was no meteorite?

Kulik still "broke through" the expedition. But she did not bring results. He found no trace of a meteorite. He did not find him in the next expedition, when in the funnel, which he considered to be an unconditional meteor crater, instead of a meteorite, there was ... an old stump. This finding clearly showed that the funnel has nothing to do with the meteorite, but Kulik ... ignored it. Instead of leaving the funnel and acting in accordance with the results, he simply forbade his assistant, astronomer and meteorite specialist E.L. Krinovu, photograph stump.

Kulik was wrong. And he was unable to admit his mistake. And later, throughout the expedition, he stubbornly clung to this and several other craters, continuing fruitless attempts to clear and drill them (and drilled by hand), which were useless for the resources, strengths of his and other members of the expedition, forbidding them to conduct research anywhere nor was it other than these funnels. I did not allow Krinov to examine the swamp, where, as he thought, a meteorite could fall, he ignored the discovery by Jankowski of a stone similar to a meteorite (which later could not be found). All this, of course, did not lead to anything good. As a result of hard work, people fell ill, were frozen (Krinov was amputated his toe), Krinov left, quarreling with Kulik ... To top it off, the drill hut burned. Expedition broke up. And ultimately she returned to Leningrad, it seemed, without a significant result - apart from another confirmation of the fact that the terrible catastrophe over the Podkamennaya Tunguska nevertheless took place in 1908, and was not “an ordinary forest fire and a cyclone,” as some skeptics stated. But now we understand that in spite of all the failures, mistakes and delusions, the lion’s share of what is known about the Tunguska Diva is the results of the Kulik expeditions. The scale and nature of the damage was assessed and mapped, many samples were collected (later damaged by storage in KMET at a time when fragments of the Sikhote-Alin meteorite were sawed and polished), the nature of damage and radiation burns on trees was described in detail. We also managed to conduct quite extensive magnetic measurements, which showed: there are no large magnetic masses in this place.

Kulik’s dream of finding the Tungus meteorite did not come true. He only once again returned to Podkamennaya Tunguska - when under his leadership aerial photography was carried out of a part of the area of ​​the fall, which confirmed the radial character of the fall of the forest. A new expedition planned in 1940 did not take place, and in 41 Kulik volunteered for the front, was captured and died of typhoid there, and the meteorite was forgotten for a long time. In 1947, it was eclipsed by another “meteorite of the century” - Sikhote-Alin. However, in 1949 E.L. Krinov published a monograph summarizing the research conducted during the Kulik expeditions.

Versions and fantasies

The first to recall the Tunguska diva was science fiction writer Alexander Kazantsev, who noticed the extraordinary similarity of that very strange earthquake recorded at the Irkutsk Observatory, with those seismic waves that were recorded after the “second gift from the Americans of Japan” - the explosion in Nagasaki.

If Kazantsev had been a careful and careful scientist in his judgments, he would have made the right conclusion: the explosion did not occur when he struck the surface, but was airborne, and he would have stopped for a while. But Kazantsev was a science fiction writer and fantasy caught him and carried him. That's it with the Tunguska meteorite: there was no meteorite, but there was an alien ship that exploded when approaching the Earth. And this explosion was nuclear. And everything becomes clear: and why a thorough search for a meteorite did not give a result - the explosion turned into a plasma and dispersed into space any possible remnants and fragments of a ship, and what caused such a nature of the forest fall, and where did those strange atmospheric phenomena, which were observed after the blast.

This hypothesis was separated from its carrier - a science fiction story, like a satellite from a rocket, and went on an independent flight. She had many supporters who began to consider her as a very serious hypothesis. Especially a lot of them became after the flight of Gagarin.

There were other hypotheses - one more original than the other. In some, the cosmic origin of the explosion was generally denied - for example, it occurred in a giant cloud of an air-gas mixture ignited by lightning. Or it was a blast of giant ball lightning. In others, the space object was present, but it had an exotic nature — a solar plasmoid, a clot of antimatter, a laser beam of aliens from the 61st Cygnus, and even a black hole.
Or whatever you like: these are all Nikola Tesla’s experiments with his towers!

The hypothesis, described in a humorous form by the Strugatskys in “Monday ...” about an alien ship moving in the opposite direction - counter-attacks, was also quite seriously expressed.


The general direction was correctly set by Kazantsev's assumptions: no one doubted that the explosion occurred at a high altitude. This was evidenced by the absence of a crater and a standing forest at the epicenter. But the fantastic part played a bad joke with the researchers of the Tunguska meteorite: fictional data about Evenks, who were allegedly sick with radiation sickness, high levels of radioactivity in these places, and a mushroom cloud, are still found in quite serious sources.

The search continues

Meanwhile, the expeditions resumed at the end of the fifties (an expedition led by KP Florensky in 1958, the Comprehensive Amateur Expedition of 1959, and others) on Podkamennaya Tunguska confirmed the absence of any traces of meteoritic matter - even in microscopic form. Earlier, a large amount of iron-nickel particles of meteorite origin was found in Kulik’s samples, from which it was concluded that the meteorite was iron. However, all samples of the magnetic fraction, which were analyzed immediately on the spot, invariably showed the absence of nickel - that is, they had nothing to do with the space substance (nickel in meteorites is always an iron satellite). There was no meteoric iron in the samples left by Kulik to be caught on Hushma. The reason for this paradox was understood later. These samples were stored in KMET, in the same place where a lot of iron meteorites lay, where they were sawed, polished, polished, poisoned and tortured them in all possible ways. They did it most intensively after the fall of the Sikhote-Alin meteorite, the fragments of which were collected by tens of tons and they all had to be characterized and described. Under these conditions, it was difficult to avoid contamination of samples with an extraneous meteorite substance.

All this said that the Tunguska body was not an iron meteorite. Even if he had completely evaporated, having exploded in the air, he would have settled on the earth with a mass of magnetite and hematite beads and dust particles of micron and submicron sizes. And these balls would inevitably contain a few percent of nickel.


Also detailed maps of the forest fall were built over its entire area, which far exceeded the part that Kulik’s expeditions explored. It became clear that the contour of the fall resembles a butterfly shape, the axis of symmetry of which coincides or is close to the direction of the probable trajectory of the car. Other effects have been mapped: radiation burns, the boundaries of a forest fire. From these data, it was possible to estimate the scale of energy release - 10 ¹⁷ J.
In addition, I had to deal with the “legacy” of Kazantsev. For this, samples were taken for measurements of radioactivity - and these measurements gave a negative result. No radioactivity was found in the skeletons of the Evenks raised from the graves, and no mention was made of anything similar to radiation sickness in medical archives.

Expeditions continued. Expeditions of the Academy of Sciences and CSEs regularly went to the site of the Tungus catastrophe. A comprehensive amateur expedition, which at that time had turned from an amateur hobby of enthusiastic people to a serious research team - was able to do what neither Kulik, nor Florensky could do - to find the substance of the Tungus meteorite! For this was applied sphagnum. It is characterized by slow growth and very stable growth and its ability to capture solid particles from the environment during growth. These particles are fixed and then pass into peat, the layer of which grows in the Podkamennaya Tunguska basin at a rate of 2 mm per year. Knowing this speed (if necessary, it can be clarified, for example, by lead-210, or by botanical signs of a catastrophe), one can find a layer of a certain age in the peat column.

For many years, cosmochemical survey was carried out with enviable persistence, consisting in the selection of sphagnum columns throughout the region, followed by the release of balls of cosmic matter from each of the layers of columns. From 1963 to 1977, 500 such speakers were selected. It was found that throughout the profile of the column, single silicate and magnetite beads were observed, associated with the precipitation of meteorites burnt in the upper atmosphere. However, in a thin layer at a depth of 27-40 cm, the number of balls sharply jumped to thousands! These balls were mostly silicate. The test-richest samples were located along the flight path of the Tunguska body, and also formed a train directed north-west from the epicenter.

Not only in the form of silicate balls was found cosmic matter. It manifested itself in anomalies of the chemical and isotopic composition of the catastrophic layer. In particular, this layer was sharply enriched with carbon-14, associated not with balls, but with acute-silicate fragments. This would be an argument in favor of the hypothesis of a nuclear explosion (with nuclear explosions, neutrons convert atmospheric nitrogen-14 into carbon-14), but the origin of this radiocarbon is different: the splitting reaction. The high-energy particle of cosmic rays is capable of splitting the core of silicon-32, and one of the fragments is carbon-14, remaining where it was - in place of silicon in the crystal lattice. And this indicator proved the cosmic origin not only of balls, but also of many acute-angular particles, and also allowed to determine the total mass of the silicate substance, since the balls, as it turned out, were only an insignificant part of it, including those submicroscopic particles that were not preserved in peat or not stood out from it by conventional methods. The total amount of silicate substance released after the explosion was estimated at 4000 tons.

On the contrary, the carbon-14 content in the organic fraction of the catastrophic layer is reduced. It can be explained by the importation of a large amount of carbon of non-biological, extraterrestrial origin.

Other geochemical anomalies were found at the site of the fall. However, their interpretation is complicated by the fact that the projectile fell into the funnel. The fact is that the depression of the Southern Bog, which was persistently taken by Kulik and some subsequent researchers for a possible meteorite crater, is a paleovolcano vent, and the anomaly of the Tunguska meteorite is superimposed on the anomaly of this volcano. Nevertheless, a careful analysis of the data allowed them to be separated from each other, which made an important conclusion: the chemical composition of the cosmic substance of the catastrophic layer resembles carbonaceous chondrites of type I, but is enriched in comparison with them by volatile elements - alkali metals, bromine, lead, zinc, tin, molybdenum, and vice versa - depleted in iron, nickel and cobalt. A similar elemental composition was determined from the spectra of the Draconid meteors associated with the remains of comet Jacobini-Zinner, as well as the spectra of comet Ikeya-Seki coma during the passage of the solar corona in 1965, which confirmed one of the main hypotheses about the nature of the Tungus body - cometary.

New hypotheses

The main conclusion of Kazantsev that a series of expeditions confirmed: the explosion occurred in the air. And for the similarity he noticed with nuclear explosions, its nuclear nature was not at all necessary - the energy release of a “nuclear” scale was sufficient.

In my previous article, I mentioned the work of K. P. Stanyukovich and V. V. Fedynsky “On the Destructive Effect of Meteoric Strikes”, where it was shown that when a meteoroid collides with speeds above several kilometers per second, a striker goes instantly and target rocks in the state of heated to very high temperatures and highly compressed steam, followed by an explosion, forming a crater. The source of energy for this explosion is only the kinetic energy of the meteoroid. And this kinetic energy already with a mass of a falling body of several tons and a speed of 50 km / s is comparable to the energy release of a small nuclear explosion.

However, there was no crater on Podkamennaya Tunguska. The explosion was in the air. What caused it?
Unlike science fiction writers and inventors of homegrown hypotheses, scientists did not need to look for a source of explosion energy. But it was necessary to find a mechanism for instantaneously, explosively slowing the meteoroid in the air. Such a mechanism was known by that time - progressive crushing of the body by the oncoming air flow. In this case, both drag and tearing forces on each of the fragments grow avalanche, which ultimately should lead to the transformation of a meteoroid into a swarm of particles, which is decelerated at once, releasing kinetic energy in the form of heat. This effect was already a little familiar to scientists for the destruction of the Sikhote-Alin meteorite, where it did not go so far. Apparently, the Tunguska body was much less durable and its fragmentation was much more intense than that of the iron Sikhote-Alin.

Rejecting the fantastic hypotheses, it was necessary to answer a bunch of questions. What was the Tunguska body? Carboniferous chondrite? Ice core comet? Loose "snowball" with very low density? What was the mechanism of explosive destruction and why did the shock wave form the contour of a butterfly? What was the exact trajectory of the Tunguska body when entering the atmosphere and its orbit?

The question with the butterfly was solved simply by experiment. The researchers used Wood's method to understand how the bomb was set up and where the old Buick was blown up, you have to go to the dynamite dumper and blow up some old Buicks. MA Tsikulin and I. T. Zotkin did the same, who decided to simulate the simultaneous impact of an explosion wave and a ballistic wave on a forest model, which they made from matches. And the shock waves they created with the help of explosives. The ballistic wave from a Tunguska body flying at hypersonic speed was imitated by a shock wave from a detonation cord, initiated from one end (a detonation wave propagating along the cord at a speed of several kilometers per second propagates along the cord and goes into the air in the form of a shock cone, resembling a Mach cone), and at the end of the cord a trotyl charge was placed, which gave a spherical blast wave in the final. And with a certain inclination of the cord above the forest of matches, that very figure of a butterfly fallout and a “dead forest” from a standing match at the epicenter was obtained. One mystery has become less. Then, of course, they used a computer and modeled the process of tree turning by the action of two shock waves - and this allowed the form of the fall to quantify the explosion energy and the slope of the trajectory.
The discovery and analysis of the substance of the Tunguska body made it possible not to make an unsubstantiated assumption about the nature of the body, but to make a reasonable assumption about its cometary nature, which by now has become almost universally accepted. The “loose snowball” model, popular at some point, was rejected - it did not correspond to the data on the nature of cometary nuclei and such a “snowball” would have collapsed too soon - already in the stratosphere, if it could even survive before it collided with Earth’s atmosphere.

He could not resist the theoretical physicists and the mechanism of explosive destruction. And again, their calculations pointed to the cometary nucleus, which entered the atmosphere at a speed of 30 km / s.
So, there is no longer any secret of the Tunguska meteorite? No, he still has many puzzles.There are still disputes over its trajectory - different observations and calculations contradict each other (this can be partially explained by the possible complex shape of the cometary nucleus, due to which this nucleus could “maneuver” by flying first along a gentle trajectory and then “pecking” "At an angle of 40 °, corresponding to the nature of the fall). And there are strange things at all. For example, the nature of a sharp increase in the growth of surviving trees in the disaster zone is not clear. The reason for the abnormally high mutation rate is unclear — the last argument, for which, like a straw, the supporters of the hypothesis of a nuclear or annihilation explosion clung.

Younger brothers of the Tunguska meteorite

And the most important discovery of recent times is that the Tunguska meteorite in general is not such a unique phenomenon. Such fireballs, the path of which ends with a powerful explosion, have been observed during “post-tungus” time more than once.

This was helped by the so-called Prairie network of car observation in the USA, which showed that “Tungus meteorites” of different caliber fall almost every year, without producing such a resonance only because their explosion occurs too high or outside populated areas. Of course, fragments of the cometary substance “Tunguska caliber” are rare, and those “younger brothers” that fall every year are much smaller and produce an incomparable effect.
However, the Vitim bolide produced an effect very similar to the Tungus (only much smaller) - a similar forest fallout in the form of a “butterfly”, despite the very modest size and mass of the original body. And the recent Chelyabinsk meteorite, although it is rather the Tunguska cousin - it was not the nucleus of a comet and after the explosion we can hold its non-evaporated remnants in our hands - having exploded it led to quite serious consequences. And not surprisingly - the strength of his explosion was about half a megaton. There was also the Borovsky car of 1934, which also exploded over the Kaluga region with great force. So race cars ending their way with powerful, “nuclear” scale, explosions are not a rare exception. Perhaps they are more frequent than those ending in the fall of meteorites.
A trace resembling the Tungus “butterfly” was discovered on ... Mars. True, the scale of this trace is disproportionately larger. This is the North Ocean, which, according to some scientists, was formed during a giant air explosion, the shock wave from which washed the crust of Mars, wiping off ancient elements of the relief. But for this, Mars had to have a powerful and extended atmosphere. Similar assumptions exist regarding Pluto’s heart. However, these are marginal hypotheses.

* * *

The problem of the Tunguska meteorite has been worrying and continues to worry for several generations of researchers, enthusiasts and just lovers of the whole mysterious and unknown. But it is necessary to distinguish scientific hypotheses and research results from a layer of sediment of fantastic fabrications, thick as sediments on the ocean floor. Its presence should always be remembered by those who decided to dive into this topic.

At KPDV picture of Sergey Krasnov "Tungus meteorite." Illustration with a butterfly from the book: Bronschten, VA Meteors, meteorites, meteoroids. M .: Science. 1987. Drawing with the unfortunate Photon from “Monday” - Evgeny Migunov.