The most ancient meteorite, the same age as the solar system, a fragment of the planet's embryo, a unique artifact - all these epithets refer to the Seimchan meteorite. He witnessed the life of mammoths and the ice age, and his detailed study provides an opportunity to learn how the young Earth was formed.
How the find was discovered
The first fragment of a meteorite was found in the summer of 1967, during a geological route. Such expeditions are carried out to detect signs of mineral deposits in the study area. A strange shiny block weighing 272 kg was found by geologist F. Mednikov in a stream. After research in the Moscow laboratory, the fragment was attributed to the iron type of meteorites that are found everywhere on the Earth's surface, and this event was forgotten for a while.
The story of the Seimchan meteorite is full of drama. In October of the same year, geologists found another fragment weighing about 50 kg. But sincethese pieces consisted of iron, they did not attract the attention of scientists. However, on the black market, meteorites and such fragments are valued very highly, sometimes more expensive than precious metals.
Over the years, the fragments scattered throughout the territory of this area were collected by black diggers. Subsequently, scientists discovered that the meteorite has a heterogeneous structure and belongs to a very rare variety - pallasite. But time has been lost. The largest rare find in Russia is almost lost.
Fragments of a celestial body are still being discovered today, especially after the "meteorite fever" that covered the local population after the fall of the Chelyabinsk meteorite. On the black market, the price for half a kilogram samples reaches 200 thousand rubles.
Where did the meteorite fall?
The meteorite impact site is located near the urban-type settlement of Seimchan, which is located about 500 km from Magadan. From the village, geologists traveled another 150 km by helicopter. The first fragment was found in a tributary of the Khekandya River. Subsequently, parts of the meteorite were also found in other tributaries of the river. Kolyma.
This is a remote and sparsely populated area, the taiga, an expedition to which requires special training. Since there are practically no roads, it is often possible to get there only with the help of a helicopter or an all-terrain vehicle. Despite these difficulties, meteorite hunters have removed from here, according to some estimates, already 30 tons of fragments of a cosmic body. The total weight of the meteorite is estimated at 60 tons.
Chemical composition
Meteorite Seimchan is inmostly made of nickel meteoric iron. The content of these two metals in the alloy varies, and on the cut of the samples a beautiful pattern is revealed in the form of intersecting shiny stripes, ribbons and polygonal areas. The distribution of nickel in an iron base and the metal streaks may provide an answer to the question of how new bodies appear in space.
The meteorite is also characterized by an abnormally high content of iridium. Another feature is that olivine inclusions are very unevenly scattered in the samples. Fragments mined from the crash site can be either pure metal fragments or contain olivine in large quantities.
Unusual properties of the Seimchan meteorite
One of the large pieces of this meteorite from a private collection was sawn at a factory in Chelyabinsk. Despite the fact that the samples have lain in the water for millennia, they are only slightly covered with rust. No less interesting is the hypothesis of why fragments are found precisely in streams and rivers. Perhaps the meteorite fell into the glacier. As it melted, the stones moved little by little from the mountains to the streams.
Meteorite material has unique properties that can be compared to high quality, very tough stainless steel. And when thin sections are illuminated, it demonstrates the unearthly beauty of olivine of cosmic origin. There are no more than 38 such stony iron meteorites worldwide.
The age of the Seimchan meteorite
The age of this unusualcelestial body is amazing - it is the same age as our Sun, that is, it appeared more than 4 billion years ago. Researchers believe that it may be the oldest meteorite that fell to Earth in the entire history of our planet. Perhaps this is a fragment of a new, once born young planet in space.
This hypothesis is confirmed by the fact that such a combination of materials (stone and iron) can only be found at the boundary of the core and mantle. The structure is finally formed first as a result of strong heating, and then after prolonged cooling in space for millions of years. It is impossible to recreate such conditions on Earth.
Cosmologists suggest that billions of years ago there were a large number of microplanets in space. Subsequently, they gathered in larger ones. This piece broke off from one of them, which, after traveling in outer space, entered the atmosphere of our planet and fell like a meteor shower over an area of about 15 km2. This happened, according to various estimates, from 2 to 100 thousand years ago.
At the moment, scientists are trying to find out from which part of the universe this meteorite flew in, to accurately estimate its age. It is possible that new sections of samples will also reveal those substances that took part in the origin of life in our solar system.
