Features of the search for fallen meteorites. Finding iron meteorites with a metal detector How to search for meteorites
The fall of a meteorite is an amazing, very short, incomprehensible and always unexpected phenomenon that causes horror and worship from an unenlightened observer. Therefore, descriptions of meteorite falls are available in many chronicle sources. The oldest of these is found in a Chinese manuscript and dates back to 654 BC. They are recorded by Greek, Roman and medieval historians. Of course, stones that fell from the sky were revered as saints and served as an object of religious worship. However, meteoric iron, which was sometimes found by people in ancient times, was used to make various tools, and it can be assumed that the first iron that mankind met was of cosmic origin.
In Russian chronicles, the earliest mention of a meteorite fall dates back to 1091 (Laurentian Chronicle). Among the most significant are the falls in Veliky Ustyug (1290), Veliky Novgorod (1212 and 1421), near the village of Novye Ergi (1662). In the annals, the fall of a meteorite was considered a bad omen. There have been repeated attempts to search for fallen stones at the sites of the falls, but all of them were unsuccessful. Until now, not a single meteorite has been found on the territory of Russia, the fall of which is recorded in the chronicle sources.
On the other hand, a lot of other meteorites have been collected over the past 350 years, and most of them are in the meteorite collection of the Russian Academy of Sciences, one of the oldest and richest meteorite collections in the world. The collection contains about 180 domestic and over 800 foreign meteorites (more than 16 thousand samples) of almost all types from 45 countries of the world.
Part of this collection is exhibited at the Mineralogical Museum. AE Fersman of the Russian Academy of Sciences, where a map of the country hangs on the wall, on which the places of meteorite finds are marked. An interesting detail - beyond the Urals, almost all finds are concentrated along the Trans-Siberian Railway. This does not mean that meteorites fell near the mainline; they are simply found where people live. And they fall more or less evenly throughout the planet. In some places, such as certain areas in Antarctica, they can concentrate for thousands of years and are clearly visible against the background of ice and snow. Thanks to this, Japanese and American scientists have collected thousands of meteorite samples there.
Rice. 42. Meteorite Sikhote-Alin in the Mineralogical Museum. A. E. Fersman. The largest specimen found - 1745 kg
They are also noticeable in sandy deserts. So, collectors, moving by car across the deserts of Oman, find hundreds of meteorites, including rare samples from the Moon and Mars. Search engines sometimes find heavy, rusty stones, but not everyone guesses that it may be a meteorite.
In the hot summer of 2000, Oleg Nikolaevich Guskov, returning home after picking mushrooms in the vicinity of the village of Dronino, Kasimovsky District, Ryazan Region, noticed a rusty piece of metal sticking out of the ground. It was not possible to pull it out with a knife. Oleg thought it might be a meteorite, went home for a shovel and a wheelbarrow and brought him home. For two years the piece of iron lay in the garden until his hands reached him. Oleg Nikolaevich sawed off a piece and took it to the meteoritics laboratory of the GEOKHI RAS to test his assumption. The examination showed that the Dronin iron, in fact, is of meteorite origin. The undertaken expedition with the help of a metal detector discovered more than 250 meteorite fragments with a total weight of about 550 kg. This is the third iron rain discovered on the territory of Russia over the past 250 years.
Rice. 43.O.N. Guskov with the Dronino meteorite he found
The collected meteorite fragments are highly oxidized, indicating a significant age of fall. The city of Kasimov (originally Meshchersky Gorodok, where Prince Alexander Nevsky died) was founded in 1152 by Yuri Dolgoruky and is located just 20 km from Dronin. The fall of such a meteorite (when it entered the atmosphere, it had a mass of at least 1.5 tons and an energy of about 100 tons of TNT) is an impressive phenomenon and would certainly be noticed by the local population not only in Kasimov, but also in Ryazan, Murom and even Vladimir, and would be reflected in Russian chronicles or later chronicles. However, no written news of this event has yet been found. Thus, it can be assumed that, most likely, this fall happened before the XII century. in an almost deserted area.
Meteorites fall at any time of the day or year. Small particles the size of a grain of sand do not reach the ground, burning in the atmosphere. Larger ones, sometimes reaching several tons, represent a rapidly moving fireball in the sky, called a fireball. A fiery tail stretches behind the fireball. Often, at the end of the movement, the car breaks up into parts in the air and scatters a cascade of sparks in the form of a fiery rain - an amazing sight, especially at night. Very bright fireballs can be seen during the day, even in full sunlight.
The author was lucky enough to observe the arrival of such a bright fireball in the Urals in the summer of 1949. A moon-sized fireball flew noiselessly almost overhead from northeast to southwest and disappeared over the horizon. Everything lasted 5-7 seconds. A wide dark trail remained in the cloudless sky. I don't remember hearing the sound of an explosion.
While moving in the atmosphere at cosmic speed, the surface of a meteoric body heats up to several thousand degrees. Small particles burn out before reaching the ground. Large bodies, more than 100 g, experience a sharp deceleration in the lower dense layers of the atmosphere at an altitude of 10-20 km. This section of the trajectory is called the delay region. Here the meteorite cools down, the glow stops, and it falls to the ground under the influence of gravity. Almost vertical. The fallen meteorite gets the name of the nearest settlement or other geographic object. Often, large meteorites, due to air pressure at an altitude of 10-15 km, are crushed into hundreds and thousands of fragments and fall to the ground in the form of a fiery rain.
Meteor showers are dispersed over the surface of the soil in an area that has an approximately elliptical shape (scattering ellipse).
They fall to the ground, being warm or cold, but not hot, as many think.
In rare cases, when a meteoric body has a large mass, it does not have time to be decelerated by air and strikes the ground with cosmic speed, forming a meteorite crater.
On Earth, about 140 impact craters with a diameter of up to 200 m are known, formed by the falls of cosmic bodies. In principle, there should be much more of them, like on the Moon. However, unlike the Moon, on Earth, geological processes are more intense and erase the traces of space bombardment on our planet. When a cosmic body collides with the Earth, a giant kinetic energy the impactor (space body) is spent on the formation of a crater cavity, as well as on crushing, melting and evaporation of the target material. These processes lead to the formation of unusual rocks (the so-called impactitites, in which characteristic signs impact on the target substance of high pressures and temperatures.
Rice. 44. Crushing of a large meteorite in the atmosphere
The small, 350 m in diameter, Lake Smerdyachye, located in the Shatursky district, about 140 km east of Moscow, is noticeably different from the numerous round lakes of the Moscow region by its unusual depth (40 m) and a well-defined ridge that surrounds this lake. Based on these characteristics and referring to the data of N.A. Filin from Roshal, Estonian scientists Yu.V. Kestlane and K.H. Mella in 1985 put forward the idea that Lake Smerdyachye is a meteorite crater.
Recently, employees of the Meteoritics Laboratory of the Institute of Geochemistry and Analytical Chemistry named after V.I. VI Vernadsky RAS conducted a study of the mysterious lake and confirmed that the lake is indeed a crater formed by a meteorite impact. According to preliminary data, the crater was formed about 10 thousand years ago. Thus, Lake Smerdyachye may turn out to be the closest meteorite crater to Moscow, which is a unique natural monument.
All meteorites are divided into three main classes: iron, iron-stone, and stone. Each class is subdivided into types. The most rare are ironstone meteorites, which are divided into two groups: mesosiderites and pallasites. Stone meteorites are divided into two subclasses: chondrites and achondrites. Iron meteorites are subdivided into three groups in structure: hexahedrites, octahedrites, and ataxites. Of these, the rarest are hexahedrites.
The vast majority of meteorites fall on Earth from the asteroid belt. At the same time, meteorites from the Moon and Mars were identified among the meteorites. These meteorites are the most expensive on the market (from $ 2,000 to $ 10,000 per gram).
By the nature of the detection, all meteorites are divided into falls and finds. Falls are considered meteorites observed by eyewitnesses and collected immediately after the observed deceleration of the meteorite body in the earth's atmosphere. In the case of meteor showers, new samples are usually found long after the fall.
Stony meteorites account for the majority (92.8%) of falls, with mostly chondrites (85.7%). Achondrites, iron and iron-stone meteorites account for 7.1%, 5.7% and 1.5%, respectively.
The finds are considered those meteorites, the fall of which was not observed. Their belonging to meteorites is established on the basis of their material composition.
The percentage of stone meteorites among finds is noticeably lower than among falls, since they are often difficult to distinguish from stones of earth origin. Iron meteorites are easier to identify and can be found with a metal detector not only on the surface, but also at considerable depths.
Outside, all meteorites have a so-called melting crust - this is a thin solidified melted layer 0.1-1.0 mm thick. A fresh fracture of stone meteorites is usually gray in color, and with a magnification it can be seen that the structure of the meteorite contains, throughout the fine-grained mass, small (less than 1 mm in diameter) balls called chondrules, which are mainly of silicate composition. Therefore, such meteorites are called chondrites. In terrestrial rocks, chondrules are not found at all. Therefore, the presence of chondrules is a reliable indication that the stone is a meteorite.
When working with a metal detector, sometimes so-called hot stones are encountered, which give the same clear signal as a metal object, but unlike the latter, the signal disappears when the search coil is already slightly removed from the stone. Nobody examined such stones in detail. In some cases, these are rocks containing inclusions of magnetite (iron ore), chalcopyrite (copper ore), or other electrically conductive or magnetic minerals. Sometimes such stones can be attracted by a strong magnet. Pay attention to their shape, surface, chipping, and perhaps a meteorite will be among them. Finding a new meteorite is a matter of chance and great luck. Treasures, for example, are much more common. However, in Russia there are several places where large meteor showers fell at one time and it is quite possible to find samples of meteorites there.
Sikhote-Alin meteorite. Octahedrite... This very abundant iron meteor shower fell on February 12, 1947 in the Primorsky Territory. More than 100 tons of material fell out, from which about 27 tons were collected and entered the collection of the Academy of Sciences of the Russian Academy of Sciences.
Chinge meteorite. Ataxite... Found in 1912 while washing gold in the bed of the Chinge brook in the Uryankhai region in Tuva. More than 250 kg of material was collected. Scraps of the meteorite can still be found. A large amount of meteorite iron was used by prospectors for forging nails, staples and other small items of artisanal use. So the search for such items is also of interest.
Dronino meteorite... Found in 2001 near the village of Dronino in the Kasimovsky district of the Ryazan region. Collected about 550 kg by specialists of the meteoritics laboratory of the GEOKHI RAS and about the same by enthusiastic search engines. The meteorite is highly oxidized and continues to corrode rapidly in air.
Meteorite Bragnn. Pallasite... Found in 1807 in the Gomel region. Scientists speak out on geographical basis conjecture that the events described in 1091 in the Laurentian Chronicle are associated with the fall of the large pallasite Bragin. Collected more than 1000 kg. Samples of the meteorite are still found, despite the fact that the territory of the fall is located in a closed due to Chernobyl accident zone.
Tsarev meteorite. Chondrite... On December 6, 1922, the "Giant Shooting Star" in the Astrakhan and Tsaritsyn provinces caused panic among the local population. However, scientists have not been able to find traces of the meteorite. Only in 1968, when plowing the fields of the Leninsky state farm in the Volgograd region, there were many ordinary stones caused plows to break. Another 11 years passed before the Committee on Meteorites from electric welder B.G. Nikiforov received a parcel with samples of these stones. Tsarev meteor shower - the largest fall of a stone meteorite on the territory of the USSR. Collected more than 1200 kg. But, for sure, you can find many more samples. The search, however, is complicated by the strong mineralization of the soil in the area.
Pervomaisky village. Chondrite... It fell on December 26, 1933 in the Vladimir region behind Yuryev-Polsky, scattering like a fireworks cascade of sparks and bursting out for tens of kilometers with thunderous rumblings and a long rumble that did not stop. In April - May, dozens of meteorites with a total weight of 49 kg were collected in the fields. You can try to look for additional copies.
The search for iron meteorites and pallasites does not present any particular difficulties in technical terms, since even inexpensive instruments react to them quite clearly. However, large specimens are located at a depth of 1-1.5 m and for their detection it is required to use sensitive instruments - Spectrum XLT, MXT, Tejon, "Kornet" and others. When searching for stone meteorites, the iron content of which is insignificant, it is necessary to use only sensitive devices, it is also desirable to have a strong magnet with you, which attracts almost all stone meteorites.
What if you find a rock that you suspect is a meteorite? In this case, the Meteoritics Laboratory of the GEOKHI RAS recommends the following.
"You can cut off a small piece of the sample (10-15 g) and send a simple parcel post to the address of the laboratory. Attach a letter consisting of the following points to the parcel:
- your last name, first name, patronymic and the address at which we can contact you,
- a description of the circumstances of the discovery (for example, "I saw the flight of a bright fireball, I found an unusual stone at the supposed place of the fall" or "while plowing the field, I found a heavy magnetic rock, which made me suspect that it was a meteorite";
- date of discovery;
- indication of the place of discovery and the nearest regional center;
- sample weight;
- its properties (color of the surface and chips, rock structure, magnetism, presence of metal inclusions, etc.);
- a photograph of the sample is desirable.
Upon receipt of your parcel, we undertake to perform a free qualified analysis of the sent sample and inform you of its results as soon as possible, even if it does not turn out to be a meteorite.
If we are really dealing with a meteorite, then further we will be guided by the rules established by the International Meteorite Nomenclature Committee, and by mutual agreements
According to the rules of the Nomenclature Committee, for registration in the International Catalog of Meteorites, it is necessary that 20% of the sample is in a scientific institution. In our case, the laboratory of meteorics at the Institute of Geochemistry and Analytical Chemistry named after V.I. Vernadsky RAS is the keeper of the Meteorite collection of the Russian Academy of Sciences and, thus, meets the specified requirement. You can consider this 20% as a payment for painstaking analyzes required to classify a meteorite and register it in the International Meteorite Catalog.
You have the right to dispose of the remaining 80% at your own discretion. From our side, we, of course, would like to get the maximum mass of the sample, since any meteorite is individual and carries a lot of interesting information about the processes that took place in our solar system. It is sad if even a small fraction of it is lost to science. In Soviet times, it was the norm to pay a monetary reward to a person who found a meteorite. In our time of transition, targeted funds are not allocated for this, but we will, as far as we can, try to reward the desire of a person to help science. I would also like to note that the fabulous prices for meteorites on the foreign market reported in the press are not entirely true. Yes, there are very few very rare meteorites highly prized by private collectors. However, the bulk of meteorites have little value on the market, and it is unlikely that the possession of a meteorite will make a person's life prosperous. And it is very difficult to sell a meteorite in our country, it can only be done abroad. Therefore, we offer you an honest dialogue, as a result of which we will come to the most satisfying conditions for all of us.
Employees of the Meteoritics Laboratory of the GEOKHI RAS ".
The address of the meteoritics laboratory: Moscow, 119991, Kosygina str., 19; Tel. (7-495) -939 fax: (7-495) 938-20-54;
e-mail: [email protected]".
In times Soviet power bonuses for the finds of meteorites were paid regularly on the basis of various regulatory documents, for example, Resolution No. 13095 SNK dated 12.05.41, Order of the Council of Ministers of the USSR No. 7501 dated 4.04.52, Regulations on the Museum Fund of the USSR No. 273 dated 26.07.65, etc. Size bonuses, of course, varied. For example, for finding the place of the observed fall of the Tsarev meteorite in 1922, the Academy promised to pay 100 gold rubles. This place was found only in 1979, and the premium paid was 400 rubles.
During the years of perestroika, the payment of meteorite premiums stopped. There was no money and no new meteorite finds. In 2003, the Academy of Sciences announced the resumption of the practice of bonuses. This year, two prizes were paid for the discovery of the Dronino meteor shower in the amount of 30 and 10 thousand rubles.
The prize for finding a new meteorite will be paid in the event that the bulk of the found meteorite is transferred to the Meteorite Collection of the Russian Academy of Sciences or for assistance in collecting specimens of a new meteor shower. The Meteoritics Laboratory of the GEOKHI RAS records the fact of the transfer of the meteorite to the Meteorite collection of the Russian Academy of Sciences or assistance in their search and applies for a prize. The amount of the bonus will be determined by the type of meteorite found.
Used materials from the site meteorites.ru
If three bright meteors had not swept across the sky over the South China Sea seven years ago, Zhang Bo would have remained an office worker in Shanghai. Bright flashes lit up not only the sky, but also Zhang's life.
“I was looking at the sky all night, I could not close my eyes, because I kept thinking and thinking, what happens to the cosmic material that falls to the earth,”- says Zhang.
Zhang is 34, and has already become one of the main meteorite explorers in China. His passion leads him on travels around the world in search of cosmic bodies. Last month, he sent 4 wonderful meteorites to the new Shanghai Planetarium, which is still under construction and is due to open in 2020.
Among the gifts to the planetarium are one lunar shard, a sample of a meteorite that fell in Qinghai province in August 2016, and a 10-kilogram stone that looks like a gold bar found in Xinjiang Uygur Autonomous Region.
“I consider it my duty to try to awaken interest in meteorites among people, especially among children,” Zhang says.
The road to heaven was winding. Zhang graduated law university, completed an internship at the prosecutor's office. He subsequently ran a gym and later developed the family's jewelry business. Now his only passion is meteorites.
At first it was difficult, he says, because in China there was almost no such direction as the study of meteorites. And Zhang had to conduct his own research using libraries and the Internet. He contacted the Shanghai Observatory, hoping to find experts on meteorites there, but he was told that there are no such specialists in the state. However, he was advised to go to the observatory in Nanjing, the capital of Jiangsu province. However, the enthusiast was not accepted there - he did not go further than the guard. Random people they were not accepted there.
Entrance to the Zijinshan Observatory in Nanjing.
But that didn't stop Zhang. He managed to get to the annual open event held with the participation of the observatory staff, and there he met Xu Weibao, who later became Zhang's mentor on meteorites.
Within four years, Zhang turned his life around and completely immersed himself in the study of meteorites. He studied books on rocks and minerals, paid close attention to the latest scientific reports from NASA. He learned the names of the breeds on English language to read foreign magazines.
“I didn’t do anything in those years, except for research. It seemed to me that I went to university again. It was difficult, but every minute brought me pleasure ",- says our hero.
Every year, around the time of the Chinese Lunar New Year, he flies to a small town in the United States located in the desert in Arizona. This is a real pilgrimage site for meteorite hunters. There is a show - sale of precious stones, relics and fragments of meteorites (We seem to know what kind of town it is. The Chinese article doesn’t mention it, but it’s obviously Tucson. ” approx. MDRegion).
Prices for meteorites there can reach up to 10 thousand US dollars, depending on the rarity of the fragment. Zhang was once sold a fake there for $ 8,700. So he realized how important it is to understand the composition of meteorites on his own.
In 2013, Zhang began his own search for rocks from space. “All the meteorites I bought were found by people. If they can find, then why can't I? "- the search engine reasoned.
He began his search in the Sonoran Desert on the border of the United States and Mexico after learning that many meteorites had been found there earlier. This is a dangerous region, as the borderlands are usually crawling with gangs and drug dealers. Zhang shares that he was often approached by repulsive personalities who mistook him for an Asian drug dealer. Also, living in a tent in the desert, Zhang was afraid of predators.
“I never managed to find anything then, but it was an unforgettable experience,” Zhang says.
His further expeditions were among the snow-covered fields of Siberia and remote deserts in the north-western region of China Xinjiang. He met wolves and bears, and found himself trapped in the fiercest storms.
He found his first meteorite in the Sahara Desert in 2014. Zhang was about to fry eggs on the hot hood of his SUV when he suddenly saw a pile of black stones next to the car, which stood out against the background of yellow sand. He immediately knew what it was. These were fragments of a meteorite.
He was so dumbfounded that he froze in place for a moment, just staring at the stones.
“I felt surprisingly calm, he says. "I just couldn't believe that I found them so unexpectedly."
After laboratory tests, it turned out that these stones are indeed meteorites that arrived on Earth from the asteroid belt between Mars and Jupiter.
“Luck is the most important element in finding meteorites, far more important than experience. You can devote your whole life to searching and find nothing. It's like a lottery ",- says Zhang.
Zhang uses NASA reports, history books, and eyewitness accounts to determine where to go next. In August 2016, one of his sources told him about a meteorite that fell in Qinghai province. Zhang Bo immediately went to the area and found a fragment of a meteorite, which he later donated for the new planetarium in Shanghai.
By the way, old archives and ancient poems are also good sources indicating astronomical events - including the fall of meteorites. Zhang says he read the story of a shooting star that fell at Nandana in Guangxi Zhuang province in 1516. And went to the highlands. He eventually found two meteorite fragments that a local farmer used as bricks to build a pigsty.
During a trip to Xinjiang in 2012, Zhang heard ancient myth about the "tear of god" that was reported to have fallen from the sky and was used in local rituals. As the researcher understood, the "tear" could well be a meteorite. Zhang spent four years looking for this rock in the rocks. His search brought him through Mongolia to Russia. And his persistence was rewarded in 2016 when he found a rock under a layer of granite. This fragment of a cosmic body is more than 10 thousand years old, Zhang proudly admitted.
Zhang goes to the search in a jeep, takes with him a metal detector, a shovel, a GPS system, a compass, a satellite phone, a tent, a sleeping bag, a supply of food and gasoline.
“And I no longer care if I find anything. I am interested in the search process itself ”, Zhang says.
By the way, Zhang found some other things in his search: ancient coins, arrows, human skeletons, elements of the uniform of soldiers of the Qing dynasty (1644-1911).
Sometimes, at the old docks near the Huangpu River in Shanghai, Zhang gives small workshops for meteorite hunters, and shows his finds there.
“Meteorites are a form of my life. The stones do not speak, but they bring peace to my soul when I am among them. "
Who would not want to have at their disposal a real meteorite that flew from the depths of space. After all, if you think about it, in fact, it is no less valuable than the lunar soil brought by both automatic stations and astronauts. Although, the meteorite may be even more interesting and valuable. It is possible that a piece of the surface of Mars, the remnant of the hypothetical planet Phaethon, or, in general, a particle of material from deep space, from which our solar system was created, will fall into the hands of a meteorite seeker.
It's no secret that meteorites are not only a valuable material for scientific research, but also have a serious market value. Far from being enthusiasts, but professional diggers go in search of meteorites all over the world. Often such groups are armed with last word technology. Here and metal detectors, computers, a field laboratory, and other know-how, allowing you to identify a space alien. Such groups rarely travel for good luck. The search is preceded by a scrupulous collection of information, both the available information about the fall of large celestial bodies, and information gleaned from the annals, the Internet, news channels, even social networks, where someone shared information about the flight of a bright fireball. And the meteor hunters are right there.
Note that a gram of a meteorite costs from $ 1 on the black market. So, hunters are not always driven by a thirst for knowledge and a desire to touch space. More often than not, everything rests on the banal cost of a meteorite. Such a find weighing a dozen kilograms will easily cost on the black market like a good foreign car.
Is it worth trying his luck for a simple man in the street, a lover of astronomy, a person who just wants to feel awe from a grain of sand, which was destined to travel in outer space for billions of years?
"Grains" of the Universe.
Oddly enough, finding a meteorite is not as difficult as it might seem at first glance. But we are talking about very small fragments, just grains of sand. The discovery of a large meteorite of both scientific and material value is still a great success. But beginners are lucky. It is worth noting that about 2-3% of the dust in your apartment is occupied by nothing more than a meteorite substance. Every day, from 30 to 150 -200 tons of meteorite matter is dumped on our planet. But all this is distributed over the surface of our planet. In the overwhelming amount, tons of microscopic meteorites and meteorite dust burst into the atmosphere every second. Basically, they all burn up in the upper atmosphere. By the way, it became well known about meteorite dust at the dawn of astronautics. At the first orbital stations, they already noticed that from the constant bombardment of windows with microscopic dust particles, they eventually become dull. Larger meteorites burn up at an altitude of 60-40 km above the ground. Having flashed as a bright star for a split second, they scatter into thousands of microscopic fragments, which are deposited as dust on our planet. But more or less large stones, the size of a tennis ball or more, often do not have time to completely burn out, and, having drawn a fireball across the sky, fall as a meteorite onto the planet. It all depends on the angle at which the celestial body entered the atmosphere, what was its speed relative to the Earth, what is its mass and composition. All this affects what can fly to the surface, small fragments or an impressive stone. On average, every year 25,000 meteorites, with a total mass of 21 tons, reach the Earth's surface. It is clear that meteorites fall almost everywhere and always. And, therefore, you can find a meteorite anywhere. Even at my dacha in the garden. First of all, you need to know well what a meteorite looks like, and how to distinguish it from ordinary stones and pieces of iron.
Let's give the first piece of advice. You should not go into the field on the very first day and collect all the stones and pieces of iron in a row. It is unlikely that with this approach it will be possible to find at least something. If you decide to become a meteorite seeker, you should always have a magnifying glass and a good magnet in your pocket. Let's start looking for the simplest and most win-win. First of all, we arm ourselves with a broom, a brush and occupy the roof, where you are allowed to climb. This can be the roof of both a high-rise building, and the roof of an ordinary village house. A garage roof is especially valuable if it is flat. Also, an excellent place to search will be an area where water flows from roofs and snow falls in the spring. This is where you should start your search for micrometeorites.
Working with a brush or a broom, we collect everything that we find on the roof. We especially carefully inspect slate cracks, roofing felt fastening strips, all kinds of damage and cavities where a meteorite can get stuck. It is far from being such a rarity when meteorites weighing several grams get stuck in the roofs of houses and can lie there for a single year. We carefully sweep everything into a container. Together with dust and grains of sand, old foliage, moss, twigs and twigs will fall. Now we fill the collected garbage with water and everything that is of organic origin, like branches, foliage, fine dust, simply floats up. Stir well, drain the cloudy liquid, after letting it settle for about 60-80 seconds. Now let's dry what's left on the bottom. This sand mixed with small pebbles is of interest to us. We begin to search among all this for that grain of sand that has traveled billions of years in space. We take out a magnifying glass with a magnet. Iron meteorites are the most common. We carefully examine everything that sticks to the magnet.
Needless to say, we immediately throw out nails, small shavings, which, it is not known how, got to the roof. Everything that has a man-made origin is not difficult to find out. But everything that has an irregular shape is the most interesting to us. Small pebbles that are magnetized and have a brown or black color are the most interesting to us. Most of the sand adhering to the magnet will be of meteoric origin, unless your house is located near a metallurgical plant or an engineering plant. We do the same with the ground under the roof of the house, the drain. Also, walking through the forest, field, when the grass is mowed, or when the snow has just melted, we select suspicious stones that meet the signs described in the article. If, when looking through a magnifying glass, the places of melting are visible, or if the needle managed to scratch a dark layer and metal flashed under it, then we can safely assume that you have a tiny heavenly wanderer in your hands.
Almost all meteorites contain iron. The type to which the meteorite belongs depends on its quantity. More information about meteorites can be found on the Internet. We will talk about how to recognize a meteorite in general and not confuse it with completely terrestrial material.
Meteorites are classified into three main groups. Iron meteorites are, in fact, a monolithic piece of iron. Such a meteorite can consist of both pure iron and include nickel, less often other metals. Ironstone meteorites are a type of metal sponge interspersed with minerals such as olivine.
Stone meteorites are the rarest and most difficult to distinguish from ordinary earth stones. On the cleavage, they are interspersed in the form of silicate balls (chondrules) and metal particles. By the way, if you find the same silicate balls in the sand from the roof, then you can safely say that they are of purely cosmic origin.
Pure stone meteorites are rare. But even they have metal. Consequently, the meteorite deflects the compass needle and is attracted by the magnet. Naturally, the more it is on the surface of the earth and in contact with water, the more iron oxide will be on it. By the way, it is the humid climate that is the main killer of meteorites. Oxidation leads to the destruction of the meteorite.
Further, regmaglipts will be observed near the meteorite. These are pits and cavities that are formed during exposure to high temperatures when it flies through the atmosphere. But often a meteorite can be smooth and not have such depressions and pits. This happens when a meteorite explodes at a high altitude, and its small parts, like shrapnel, fly in different directions. If the shards rotate, then they will have an irregular shape, dotted with regmaglipts. But those that did not have rotation, often have the shape of a bullet, a cone, and may look like a piece of the tip of a canine tooth. At the end of such meteorites, there will be visible traces of a float, which was blown off when the atmosphere passed backward. On the conical part, the meteorite will have a melting crust only microns or a few microns thick. But at the end up to a millimeter. It must be remembered that a meteorite can never burn out completely and have a porous structure.
If you come across something like this, it is most likely slag, which has a completely terrestrial origin, or foundry waste. Also, a meteorite cannot contain easily crumbling substances like chalk, spar or gypsum. Therefore, if you still collected material in the field, on the road, under the roof of structures, where everything was washed off the roof with snow and water, where there may be larger suspicious objects, after scraping you will see that it easily collapses and crumbles, most likely it is not a meteorite.
If you are lucky and you have a decent suspicious object in your hands that magnetises well, deflects the compass needle, having a melting crust, you should try to polish one part of it. If the dimensions allow, then simply rub it on fine sandpaper, or, holding it in a vice, work with a file. Then, try to polish the saw cut. Etching nitric acid polished saw cut (or saw cut if the meteorite is rather large), the Widmanstätt structure will immediately become visible.
Another important detail. A meteorite always has a higher density than any rock. It's heavy. Even if you take the same volume of granite and meteorite, the latter will be noticeably heavier. If the combination of signs is enough, you can safely say that you have a space guest in your hands.
Most often, meteorites are confused with metallurgical waste - slag. They have a melt, heavy weight, shiny metal inclusions. But at the same time they have a porous structure. A meteorite is never porous. Igneous rocks and magnetites are often mistaken for a meteorite as well. Their weak magnetization is confusing. But quartz crystals will be visible on the cleavage, which will even form veins. This does not happen in meteorites. And the magnetic properties of such rocks are given by the presence of magnetite, hematite, ilmenite, etc.
The knowledge described above is quite enough not to carry home all the stones in a row. Also, all of the above will allow the reader not to pass by some, at first glance, cobblestone lying on the road, dug out in a garden bed, or a stone lying on fresh arable land, which may turn out to be a serious instance of a meteorite that flew to us from the depths of space. Therefore, here is the last piece of advice for you - any large finds, in whole or in part, should be given to a museum. There scientists will "talk" them. Even if you can sell your stone, will not your conscience torment you that perhaps because of your greed some secret of the Universe has remained unsolved?
A meteorite that passed over the territory of the Chelyabinsk region fell into a reservoir 1 km from the city of Chebarkul. However, some places where meteorites fall on the territory of Russia have not yet been precisely established, and mankind does not even suspect the existence of many. Every year, about a thousand celestial bodies with a total mass of about two tons reach the earth's surface.
Daria Golzalez, specially for RBTH
However, some localized meteorite impact sites at various times have already been noted by tourists and meteorite seekers. RBTH has compiled the most known cases falls of meteorites in Russia, geographical coordinates which are open to anyone who wants to find a piece of the "heavenly body".
Long-known places of meteorite falls are the epicenters of "meteor fever" - often there are so many debris of meteor showers that all of them cannot be collected for a long time. For example, meteorite seekers have been combing the Siberian taiga in search of numerous "heavenly fragments" for almost a century. However, not only Siberia should be worthy of your attention if you decide to go in search of a celestial body that has fallen to Earth.
Primorsky Krai
Sikhote-Alin iron meteor shower
The Sikhote-Alin meteorite fell near the village of Beitsukhe (now the village of Meteoritnoye) of Primorsky Territory in the Ussuri taiga in the Sikhote-Alin mountains in the Far East on February 12, 1947. The meteorite shattered in the atmosphere and fell as an iron rain over an area of 35 square kilometers. At the head of the "scattering ellipse", 160 craters were found, with diameters ranging from 1 to 28 meters. The depth of the largest crater reached 6 meters, and the meteorite itself entered the ten largest meteorites in the world. Not all of its fragments have been found, many of them are still found in tree trunks, so you won't have to crawl on the ground with a metal detector in your hands.
In addition, the Sobolev Crater is located on the territory of the Primorsky Territory, which was formed about 1000 years ago. Its diameter is 53 meters.
Tyva Republic
Chinge meteorite
The first finds of fragments of the Chinge meteorite were made in 1912 on the Urgaylyk-Chinge river, the Elegest system, the Vostoyny Tanu-Ola ridge. Placer gold was discovered in the upper reaches of the river, which brought prospectors here during the "gold rush" in Tuva at the beginning of the 20th century. Massive pieces of metal (nickel iron) found by prospectors turned out to be debris of cosmic origin, and one of the mines on the Chinge brook was named "Meteorite". Finds of meteorites on this river continue to this day.
Astrakhan region
Tsarev Meteorite
The fall of the Tsarev meteorite (weighing 1225 kilograms) was observed as early as 1922, but it was found only in 1968 when plowing the fields of the Leninsky state farm. The first message about the find was received only 11 years later from the electric welder Boris Nikiforov.
To date, about eighty fragments of the Tsarev meteorite have been found. Some of them are kept in private collections, but most of them in Moscow, in the Russian Academy of Sciences. Their weight is from fifty grams to 283 kg. The Tsarev meteorite became the third largest meteorite in the history of mankind in size and weight. The search for its fragments is still underway.
Tatarstan
Kainsaz meteor shower
Tatarstan is home to the largest meteorite crater in Russia - Karlinsky crater. Its diameter is 10 km and its age is estimated at 5 million years. The crater is located west of the city of Buinsk, on the border with Chuvashia.
In total, 4 meteorites were found on the territory of Tatarstan. The largest is Kainsaz, which fell on September 13, 1937 in the Muslyumovsky district. Its fall took place on September 13, 1937 near the village. Kainsaz. A unique phenomenon was observed by local residents. The total weight of the meteorite, which disintegrated during the fall, was more than 210 kg.
Meteorite seekers began a massive pilgrimage to the village of Kainzas only at the end of the last century, and there is still time to find a large fragment.
Chelyabinsk
Kunashak meteor shower
Yesterday Chelyabinsk experienced not the first meteor shower in its history. On July 11, 1949, a meteor shower settled on an area of 194 square meters. km across the territory of the Chelyabinsk region. In total, twenty fragments were found with a total weight of almost 200 kilograms. The age of the Kunashak meteorite is relatively small: only 720 million years. On the fragments of the meteor shower, unlike other cases of falling space objects, no melting crust was found, which scientists explained by the high density of the solid matter of the meteorite itself, in contrast to the fragile melting crust, which fell off when the meteorite flew through the atmosphere.
Krasnoyarsk region
Tunguska meteorite
The remains of the Tunguska meteorite have not been found, and its origin is one of the main mysteries of the scientific community. In 1908, a fireball flew over the territory of the Yenisei River basin. The flight ended with an explosion at an altitude of 7-10 km over an unpopulated area of the taiga. The blast wave was recorded by observatories around the world, including in the Western Hemisphere. As a result of the explosion, trees were felled over an area of more than 2000 km², glass was shattered several hundred kilometers from the epicenter of the explosion. For several days, an intense glow of the sky and glowing clouds were observed in the territory from the Atlantic to central Siberia. Even now, there are many versions about the origin of this celestial body - from the consequences of the experiments of Nikola Tesla to the comet. The administration of the Krasnoyarsk Territory has developed tourist routes to the site of the fall of the Tunguska meteorite, designed, among other things, for foreign tourism.
VOH: Borodino
A meteorite fell on the eve of the Battle of Borodino into the location of the Russian artillery battery, which occupied a position near the village of Gorki. The meteorite was kept for a long time in the family of the battery commander A.I.Dietrichs and only in 1892 (80 years after the fall) was it transferred by his descendants to the Russian Academy of Sciences.
VOH: Meteor Hunters
The main magnetic measurement technology is magnetometers and gradiometers. When searching for meteorites, they are much more effective than metal detectors due to their greater depth and coverage. So, thanks to this modern technique, 20 meteorites were found in Antarctica in just 4 hours. For many meteorite hunters, their search is more than a hobby - there are cases when "seekers" have earned more than a million euros selling meteorites. And the price of a fragment can range from 300 euros to several hundred thousand. In Russia, evaluates and pays rewards for meteorites Russian Academy Science.
The author of the article - IN AND. Tsvetkov Russian Society of Meteorite LoversFinding and collecting meteorites
Meteorites are debris of cosmic bodies that, for a number of reasons, received orbits that cross the earth's orbit, and because of this, sooner or later fall to the Earth. These are quite rare objects: the number of different meteorites known on Earth for a long time did not exceed several thousand, and only the last decades have revealed places of natural concentration of meteorite matter (Antarctica, stone deserts), and their number has grown to tens of thousands. Note that we are talking here about different meteorites, each of which can be represented by many specimens (meteor showers, multiple falls). Before the era of space exploration, meteorites were the only representatives of cosmic matter available for laboratory analysis.
Basically, interest in meteorites from the very recognition of their cosmic bodies (late 18th - early 19th centuries) was shown by specialists - astronomers and mineralogists. However, these rare and spectacular objects have become the subject of attention and private collectors. Thus, the private collection of the Russian collector Yu.I. Simashko at the end of the nineteenth century numbered more than 400 items.
The final identification of a sample as a meteorite can be carried out only through a special study of its substance by chemical, mineralogical and isotopic methods. Recognition of a sample by the scientific community as a meteorite and its inclusion in the appropriate catalogs occurs only after publication in a special edition "Meteoritical Bulletin" (http://meteoriticalsociety.org/simple_t ... b_bulletin). Note that currently unnamed, unexplored and unrecorded meteorites are of little interest to collectors, unless the collector himself sets out to register a new meteorite.
On the basis of the material composition, meteorites are divided into three large classes: iron, stone and iron-stone. In turn, within the classes, groups and types are distinguished that differ from each other in composition and / or in structure.
General and more detailed information about different classes and types of meteorites should be sought in special scientific or at least popular science literature (for example: EL Krinov. Messengers of the Universe. M., 1963; VA Bronstein. Meteors, meteorites, asteroids. M., 1987; A. N. Simonenko. Meteorites - fragments of asteroids. M., 1979; R. T. Dodd. Meteorites. M., 1986). But some of the features that make it possible to at least "suspect" a sample of meteoric origin should be mentioned right away.
1. All iron meteorites contain a noticeable amount of nickel: not less than 4-5%. None of the earth's minerals contains a natural alloy of iron with nickel, therefore, analysis for nickel usually resolves the question of the meteorite origin of a metal sample ("nickel-free" meteorites have not yet been found - they are not among the observed falls, not among the tens of thousands of meteorites found in Antarctica, which is a strong statistical argument in favor of their absence in nature at all). Therefore, the found piece of nickel iron is either a meteorite or an industrial product, the material of which, however, always has a structure completely different from the structure of a meteorite.
2. The most common type of stone meteorites (chondrites) has rounded inclusions in the main matrix, which are called chondrules. They are small (the first millimeters or fractions of a millimeter) and differ from the matrix in color (usually darker). Their composition does not differ from that of the matrix, and the origin is still controversial.
3. In chondrites, inclusions of nickel iron are common (and often numerous). This makes meteorite "stones" heavier than Earth's on average. And, as a rule, they react to a magnet.
4. During internal structure stony meteorites always lack stratification and porosity is rarely observed and, moreover, large caverns, characteristic of industrial slags.
It makes sense to start searching for meteorites when you have a more or less good idea of what they look like.
The main feature of recently dropped meteorites is that their surface bears traces of interaction with the atmosphere through which they move at a very high speed (the minimum speed of a meteorite entering the earth's atmosphere is 11.2 km / s). This causes strong air friction, heating and melting of the outer surface of the meteorite. The formed layer of molten substance is immediately torn off by the flow of oncoming air and solidifies in the form of very small droplets that form the smoke trail of the fireball. At the same time, the atmosphere slows down the movement of the meteorite, and when its speed drops to the speed of free fall, the last molten layer, due to the onset of cooling, solidifies on the surface of the meteorite in the form of a thin (rarely thicker than 1 mm) so-called "melting crust". It consists of the same substance as the meteorite itself, but first melted and then solidified again. The melting crust is black in almost all cases. In most meteorites (the most common chondrite stone meteorites), it is dull, but in some types it can also be glassy.
Another feature of the surface of a freshly fallen meteorite is also associated with very fast movement through the atmosphere. Depressions and dents delimited by partitions appear on the surface, so that the whole picture resembles frozen ripples on the water. These dents are called regmaglipts. The characteristic size of the regmaglipt for a medium-sized meteorite is about one-seventh of the characteristic size of the meteorite itself; for larger or smaller samples, this ratio may vary slightly. If the meteorite rotated strongly while moving, regmaglipts may not form at all. And when the meteorite did not change its position during the flight, an "oriented" shape appears - a cone with its apex facing in the direction of motion. In this case, regmaglipts are formed mainly on the lateral surface closer to the base of the cone and have an elongated shape - "regmaglipt corolla". In such meteorites, the degree of atmospheric treatment of the frontal and rear parts of the sample differs greatly.
Meteorite matter enters the Earth constantly. If the fall occurs in a densely populated area and at a convenient time, the phenomena accompanying it (flight of a fireball, loud sounds, sometimes shaking the ground) may be noticed by casual eyewitnesses. By purposefully interviewing as many eyewitnesses as possible, one can construct a statistically probable trajectory of a meteorite in the atmosphere and look for a dropped piece of cosmic matter near the projection of its lower end onto the Earth. Occasionally, a small cloud is observed near this lower end as it falls, marking the "delay region". At this point, the meteorite already loses its cosmic speed (due to deceleration in the atmosphere), which is why it falls almost vertically. Remains of speed are retained only by very large pieces, weighing at least 100 kg. In this case (when a high intensity of optical and sound phenomena is recorded, as well as the presence of microseisms), one should look for the place of fall on the continuation of the projection of the trajectory forward along the movement of the meteorite relative to the previously indicated point. If the eyewitnesses saw the very fall of the piece to the Earth, then they obviously picked it up. Then it remains only to look for the eyewitnesses themselves and try to get the meteorite from them, offering some kind of compensation. At present, the population's idea of the possible amount of this compensation is greatly exaggerated due to the illiterate statements of journalists on television and in the press. You need to be ready for this and have with you any evidence of real prices for meteorites. The meteorites observed during the fall are called falls. Their scientific value is significantly higher than that of the finds - meteorites that fell for a long time and were not raised immediately after the fall, so the date and circumstances of their fall remain unknown. The falls are better preserved and are not contaminated with substances from the earth's environment. If the meteorite ("find") has lain long enough after the fall, its appearance changes and the meteorite becomes "difficult to recognize". The characteristic black color of the outer surface disappears: due to oxidation, it becomes brownish, or yellow, or orange. The meteorite is covered with a film of oxides, which can completely hide its initial external forms. Iron meteorites survive better than stone ones - they are more durable, and also more often attract attention as "strange" objects not related to the natural environment in which they are located. Therefore, among the finds there are more iron meteorites than stone ones. With falls, the situation is exactly the opposite, which indicates the predominance of the stony component of matter in space.
In any case, when searching for meteorites, it should be borne in mind that the most important reason to "suspect" a sample of meteorite origin is its lack of connection with environment and geological setting. The meteorite does not "look like" those objects that are constantly found in a given place.
Searches for meteorites should not be organized "out of the blue." In general, they are rarely and randomly located on the surface of the Earth. Some prerequisites are needed for organizing searches. This could be the following:
1. Observations of a very bright fireball (accompanied by powerful sounds and microseisms, illuminating the area). In this case, it is necessary, if possible, immediately after receiving the message about the car, to collect the largest possible number of observations of casual eyewitnesses. It is highly desirable that the points from which the observations were obtained should be separated from each other as long as possible. It is impossible to construct a trajectory based on observations from one place. When interviewing eyewitnesses, absolutely neutral questions should be asked. Prompting, pointing at the answer is completely unacceptable. Even if the readings are contradictory, they should be dealt with only when processing observations. It is very good if an eyewitness from the place of observation points with his hand the path of the fireball in the sky (from the very place where he saw it). In this case, you should measure the angular coordinates of two points of the visible trajectory, most often the beginning and end of the car's path. A good compass and eclimeter are used for measurements, which are easy to make from a conventional protractor and a plumb line. After processing the observations, the position of the lower point of the trajectory is determined, and searches are organized near its projection onto the Earth.
2. Messages from the population about "strange" stones and pieces of iron, once noticed by them. Such messages (including historical, that is, quite old) are found in some books (for example: I.A. RAS, etc.), as well as on some domestic sites on the Internet (http://www.meteorites.ru/; http://www.ollclubs.ru/forum/viewforum.php?f=4). The location of the find is determined with the possible accuracy from the source, the probability that the object can really be a meteorite is estimated, and after that a search is organized for it.
3. Search for new specimens of already known meteorite falls. This applies primarily to meteor showers. It is never possible to collect all the specimens of a meteor shower at once. Even meteor showers that fell very long ago (for example, the Polish Pultusk, fall of 1868) continue to provide a number of new finds. The point is not even that searches for meteorites with metal detectors have only recently come into use, and it is visually impossible to notice all instances of rain, especially heavy rain. It's just that each search method contains a greater or lesser probability of missing a meteorite, always not zero.
Meteor showers are caused by the atmospheric crushing of an originally single meteorite body. When the resulting debris moves, they are sorted by size, since small, light specimens are slowed down faster than large ones. As a result, in the zone of meteorite scattering over the Earth's surface (usually elongated in the direction of flight), individual specimens are arranged in a regular order: the larger the sample, the closer it is to the head of the scattering region. Of course, this dependence is of a statistical nature, also because sorting, in principle, occurs not by mass, but by aerodynamic quality. However, on the whole, the dependence is exactly that, which is confirmed by the distribution of meteorites over the area in the known meteor showers.
It should be borne in mind that during atmospheric crushing, large pieces are formed less than small ones. In addition, a large meteorite is easier to spot during the initial survey of the fall area. Therefore, during further investigations, the most promising places are those in which there are meteorites of small masses. Their instrumental search can bring success with high degree probabilities.
In this case, even some quantitative estimates of the search prospects are possible. Assuming that large meteorites have been collected quite completely, we will construct for them the dependence of the number of found meteorites on their mass. We extrapolate this dependence to smaller samples, and obtain the probable number of small meteorites that fell. Subtract from this number already collected small meteorites and get an estimate of the number of still undetected meteorites. Let's roughly estimate from the map the area over which they could disperse. Dividing it by the number of meteorites, we get the probable minimum area that must be viewed in order to find at least one meteorite. Having data on the speed of viewing areas, depending both on the performance of one metal detector and on the number of simultaneously used devices, it is possible to obtain an estimate of the minimum period of work. Estimates of this kind were made in 1982 during the search for specimens of the Tsarev meteor shower and gave a good match: on a field of 16 hectares, completely scanned with metal detectors, the predicted number of samples was found - two.
Calculations show that the continuous scanning technique is effective for heavy meteor showers with a high surface density of meteorite distribution. For example, for the Sikhote-Alin meteor shower, where individual points of fall in the zone of small specimens are separated not even by tens of meters, but simply by meters, it invariably leads to success. However, in last years there is a random selection of material without fixing the surveyed areas on the map, which creates difficulties in the further choice of places of work. However, the total number of dropped samples (about 100,000) suggests that in the near future this "meteorite mine" can be effectively exploited.
In Russia, there are three places where the search for meteorite samples, if properly organized, will almost certainly lead to new finds. This is the already mentioned Sikhote-Alin iron meteor shower (Primorsky Territory), the Tsarev stone meteor shower (lower Volga, Akhtuba) and, finally, the Chinge meteorite, about which it is still impossible to say with certainty whether it is a meteor shower or fragments of a crater-forming fall. Recently, the Dronino meteorite in the Ryazan region has been added to them. But this fall is very ancient, and excavations are required there.
The stone meteor shower of Pervomaisky Settlement (Vladimir region) is promising, there are meteor showers Kunashak ( Chelyabinsk region) and Kainsaz (Tatarstan). The last meteorite belongs to a rare and interesting type of carbonaceous chondrite.
It should be borne in mind that some meteorites that do not belong to meteorite showers, but have morphological features that suggest the fact of atmospheric fragmentation, are also promising for the search for new specimens. The combination of these features E.L. Krinov called "surfaces of the second kind" - weak melting, thin melting crust, undeveloped regmagliptic relief, etc. The presence of surfaces heavily treated by the atmosphere on the same sample unambiguously indicates atmospheric crushing, and, consequently, the existence of other pieces of this meteorite.
4. Suitable landscape conditions. Recently, geographic regions have been discovered in which there is a long-term natural accumulation of meteorites that have fallen over very long periods of time. This is, for example, Antarctica, where the gradual sliding of the ice "cap" to the edges of the continent in some places encounters an obstacle in the form of ridges transverse to this movement. In such places, there is an intense erosional cut of ice, and the meteorites included in it, which have fallen over a very long period of time over a very large area, come to the surface, where they are collected. Attempts to assess the effectiveness of this mechanism for other regions of the Earth (Arctic, mountain glaciers) lead to disappointing results - each time the prospective collection area is too small. Keep in mind, however, that one of the largest meteorites in the world, Cape York, is found in ice-covered Greenland.
Another situation associated with the natural accumulation of meteorites is rocky deserts. The dry, arid climate contributes to the preservation of the fallen meteorites, and the lack of population means that no one collected them. Such deserts containing a large number of meteorites different types, known in Africa, Arabia, Australia. It is very possible that there are similar areas in Kazakhstan, Central Asia and other regions of the former Soviet Union. They are completely unexplored.
Organization of field work at the proposed "meteorite site" may include different search methods:
1. Visual inspection of the area. All the "suspicious" items are collected. The places of meteorite finds are marked with some signs, and then a plan of the places of the finds is drawn up (at least visual, but better with the use of GPS or geodetic measurements).
2. Instrumental searches. As a rule, they are based on the presence of metal in meteorites (including stone). Such work began in the 20th century and involved the use of the simplest metal detectors such as army mine detectors. In our country, they were carried out in the fields of scattering of meteor showers (Sikhote-Alin, Chinge, Tsarev, etc.). Particularly successful were the work on the Sikhote-Alin, where this method collected thousands of samples of both individual surface scattering meteorites and fragments in the crater field. Currently, there are quite advanced instruments such as metal detectors used to search for meteorites.
When searching, it is possible to use other geophysical devices, for example, magnetometers. This makes sense if the presence of large magnetic masses is assumed at a considerable depth below the earth's surface.
3. Excavations. Their application can be associated with information obtained during the use of geophysical instruments. But sometimes just a trial pitting is carried out in suspicious places. For example, samples of the Chinge meteorite, initially scattered along the mountain slopes, over a long period since the fall, migrated in the direction of the mountain stream beds, where test pits are being laid.
Annual global statistics show that meteorite finds are not such a rare event. It is possible that someone who has read this article will sooner or later find an interesting stone or piece of iron that does not look like ordinary earth rocks or slags. This find may be a meteorite. And meteorites are unique samples of cosmic matter that must fall into the hands of scientists.
