Sikhote - Alinsky meteorite - With English subtitles
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Sikhote-Alin Meteorite
Subtitles: Albert Abdrakhimov
The huge meteorite fell in the area between Khabarovsk and Vladivostok
in Sikhote-Alin mountains on February 12, 1947 at 10:38 A.M. local time (46°7'N,134°40'E).
The swift meteor flight and its smocky
light could be seen for hundreds of miles.
The local artist, Medvedev, as an eyewitness,
portrayed this rare natural phenomenon.
The fall site was found by pilots.
Flying above the forest,
they noticed clearly distinguished in the
snow cone pits among the fallen trees.
Soon geologists appeared in the snow-covered taiga: Ermolyuk,
Tatarinov, Anisimovsky and Shipulin.
For three days they made off-road way in
deep snow looking for a craters.
Here they are!
The traces of a meteorite fall!
The geologists examined the damages and
counted more than 30 cone craters.
They mapped them and began
to clean up one of the craters.
Look, this is a spall of an iron meteorite!
The prospecting results has been reported to the Academy of Sciences of the USSR
The Academy organized an expedition to the fall area, headed by Academician Fesenkov.
Scientists had left for Vladivostok and routed through Iman to
Novopoltavka, the last settlement on the way of the expedition.
Here they joined by a group, whose members
had visited local villages and recorded
the testimony of hundreds witnesses of the meteorite falling.
Only 12 miles separated the expedition from the target.
But the path was very hard through the Ussury taiga.
The road was blocked by wind-fallen trees
and vernal flooded streams
Suddenly the taiga had thinned.
Look! The crater!
Another!
The third!
The whole crater field!
The camp was set up in a near birch grove.
Survey of the craters had begun.
From the pile of stones meteorite fragments were dug.
Samples were flattened with sharp and jagged edges.
These scars are signs of the impact.
Pressure at that moment reached 10000s atmospheres and
many splinters were strongly bent.
A magnet found tiny meteoritic particles in the soil.
Such iron dust saturates the whole field.
To the north from craters in the wild taiga,
the whole meteorites have been found which have not broken up at falling.
Such meteorites is called by scientists “the individuals”
These meteorites differ from splinters the melted off and original pitted surface,
as the evidence of atmospheric interaction.
On many samples the fuse metallic splashes have remained
or the hardened jets or droplets.
Drops were blown off from falling meteorites
and settled in the ground.
They have been found out at soil research.
Slightly melted off fresh breaks were exposed
on the surfaces of some individuals.
It is the evidence that all fallen meteoritic samples made
the uniform body which had broken up in the terrestrial atmosphere.
The big fragments have formed craters at falling
and had broken into thousands splinters.
The craters position was measured by the theodolitic survey.
The map was made on its base.
The trees had been damaged around the craters
Study of whole falling conditions and
the testimony of eyewitnesses, allowed
to define a meteorite way in the atmosphere and then to calculate
its orbit in interplanetary space.
It is known that there are numerous minor
planets, asteroids, between orbits of Mars and Jupiter.
Some asteroids paths crossed the orbit of the Earth.
Academician Fesenkov calculated the Sihote-Alinsky meteorite orbit
and found that it was one of small asteroids.
Moving with a speed of 40 km/s,
the meteor has caught up with the Earth,
blew through atmosphere
and broken up to fragments due to huge air resistance.
The expedition head, Academician Fesenkov, is speaking:
The value of Sihote-Alinsky falling is concluded in that it was
the first time in mankind history the crater field formation in real time
as a result of collision of a small asteroid with the Earth.
This falling obviously shows the relationship of
meteorites and asteroids and allows estimating
a role of meteorites in Solar system.
The second expedition of Academy of Sciences was directed to a taiga
for advanced meteorite collecting.
The rapid spring flood forced the scientists
to change the way of movement.
They went against a rapid Beytsukhe-river current using poles.
Then floated on the river Khanikheza
and had landed in 12 km from the craters field.
The taiga had met researchers
with dense thickets of creeping plants, prickly bushes.
The expedition was headed by the magnitologist Sergey Fanton.
The difficult way has left behind, and the
group approached the camp in a birchwood.
In a taiga again had begun to knock axes,
glades were laid, there was a preparation for aerial survey.
The recognition signs were hung on high trees,
as the reference marks for pilots.
All area of meteorite falling was photographed.
These are the aerial photos.
They were used to make an exact map.
On the map the dark circles indicate places of falling of meteorites.
The area of iron strewn field is spread out on the area about 2 sq.km
The strewn ellipse extends from the north to the south,
in a meteorite movement direction.
Simultaneously the geological study of craters field were conducted
The rock layering and its characteristics was studied.
Features of meteoric cones were sketched.
As the meteorite was iron, the magnetic method was used during searching.
The magnetic survey network was set up.
Then the terrestrial magnetic field intensity was measured by
a magnetometer in each point.
The device marked the raised intensity
of the soil, where there were meteorites
The made graphs determined the fields of
splinters or places of large meteorites.
Now it is possible to start excavation.
The large meteorite is found!
Excavations were made by combat engineers.
Meteorites pierced a soft ground on depth to 8 m.
This visually small meteorite weighs 250 kg.
Raining turned many cones into ponds.
It is hard to dig out such cone.
After water pumping out there was damp swollen clay in it.
According to magnetic surveying it should be a large meteorite here.
And it is true!
The 700 kg meteorite was taken from this pit.
Works in a taiga were carried out with breaks during 4 years.
In the winter of 1950 had been discovered the biggest crater,
with diameter of 28 meters.
Here the meteorite had fallen to rocky stones
and was shattered into set of splinters.
In the same winter the largest individual meteorite had been found.
It weighed 1745 kg.
For all time of works scientists revealed 93 cones,
collected 355 individual meteorites, and about 7000 fragments
in gross weight of 23 tons.
But not all cones were unsealed.
It has been decided to keep the third of the most typical,
having protected by tents from a bad weather.
Expeditional works had been finished.
The strewn field was declared as the state national park.
The comprehensive study of the Sihote-Alinsky meteorite was continued
in Academies of Sciences at Moscow.
Meteorites are unique extraterrestrial bodies
which directly could be studied in laboratories.
The meteoritic substance were undergone to the chemical analysis.
Analyses of many samples measured exact composition of a meteorite.
The significant abundance of nickel distinguishes
meteoritic iron from the terrestrial.
The spectral analyses of the meteorite have found out
the admixture of 26 elements.
Spectrum lines have shown that the meteorite contains copper,
germanium, chrome, gold, platinum, and
other elements known on the Earth.
The uniform distribution of admixtures shows that the Sihote-Alinsky meteorite
made a part of a large extraterrestrial body.
The study of the internal structure of a meteorite also
reveals conditions of its formation.
The surface of a meteorite etched by acid demonstrates its structure.
It is combined from separately large crystals of alloys of iron with nickel.
Such structure pointed to slow
cooling of an alloy during millions years.
Layered inclusions of various minerals were conducive to
meteorite disintegration in air.
Mechanical tests of samples have shown
that destruction occurs along these layers.
The thin parallel lines crossing each crystal
are clearly defined under a microscope.
In splinters these straight lines are bent as the result
of meteorite blow in the ground.
Various samples of the Sihote-Alinsky rain from the tiny
to large iron blocks
have filled up the richest collection of Academy of Sciences.
It represents many remarkable meteorites.
Pallas iron is a huge iron sponge with mineral grains of olivine.
Boguslavka meteorite is the single Fe-Ni crystal which has broken up at falling.
The carbon meteorites are remarkable,
because a water has been found in their composition.
The stone meteorite Nikolsky represents
a friable aggregation of many crystal balls.
All these, would seem various meteorites, have got a a common origin,
and are fragments of one or several planets.
Meteorites are close to deep terrestrial rocks.
Their study is important for knowledge of inaccessible to us Earth interiors.
Research of meteoritic substance reveals secret of planets formation
and emphasizes unity of a matter of the world surrounding us.
The richest material for science has given the Sihote-Alinsky meteorite
The End
