Iron, IIAB
Fell February 12, 1947
Primorskiy kray, Russia

At around 10:30 am on February 12, 1947, eyewitnesses in the Sikhote-Alin Mountains , Primorye, Russia , observed a large bolide brighter than the Sun that came out of the north and descended at an angle of about 41 degrees. The bright flash and the deafening sound of the fall were observed for three hundred kilometers around the point of impact not far from Luchegorsk and approximately 440 km northeast of Vladivostok . A smoke trail, estimated at 32 km long, remained in the sky for several hours.

As the meteorite traveling at a speed of about 14 km/s entered the atmosphere, it began to break apart, and the fragments fell together. At an altitude of about 5.6 km, the largest mass apparently broke up in a violent explosion.

On November 20, 1957 the Soviet Union issued a stamp for the 10th anniversary of the Sikhote-Alin meteorite shower. It reproduces a painting by P. J. Medvedev, a Russian artist who witnessed the fall: he was sitting in his window starting a sketch when the fireball appeared, so he immediately began drawing what he saw.

Because the meteorite fell during daytime, it was observed by many eyewitnesses. Evaluation of this observational data allowed V. G. Fesenkov, then chairman of the meteorite committee of the USSR Academy of Science, to estimate the meteoroid's orbit before it encountered the Earth. This orbit was ellipse-shaped, with its point of greatest distance from the sun situated within the asteroid belt, similar to many other small bodies crossing the orbit of the Earth. Such an orbit was probably created by collisions within the asteroid belt.

The site was meticulously mapped and hunded by E.L. Krinov.

An excerpt from author Roy A. Gallant's Sikhote-Alin Revisitied:

It took investigators 19 years to launch the first expedition to the Tunguska site in 1927. But only three days after the S-A strike, pilots spotted the fall site marked by a group of bright auburn patches in the snow-covered taiga. This revealed two important features of the fallit was crater-forming, and it was multiple. Two months later a team of investigators led by the well-known astronomer V. G. Fesenkov hacked their way through the nearly impenetrable taiga to the crater field. They located 122 craters, the largest of which and first to be investigated was 28 meters in diameter and 6 meters deep. Additionally they counted 78 "pits." Four years later more than 20 tons of iron-nickel fragments were in the Soviet Academy of Sciences warehouse.

E. L. Krinov, the leader of later expeditions in which Tsvetkov played a major role, concluded that the dispersion zone was 1 by 2 km with a major axis suggesting that the swarm had rained down from NNW to SSE. N. B. Divari disagreed, saying that his more than 180 eyewitness accounts of the smoke trail fixed the entry direction from NNE to SSW. Krinov said that the wind most likely blew the smoke trail off the bolide's true course. Tsvetkov's later work in 1975 was to prove Divari right, yet it is invariably Krinov's dated writings that appear in the English language scientific press. The 1975 expedition also was to cause major areas of conflict between Krinov and Tsvetkov.

Krinov was a tireless investigator and meticulous in his work, to the extent of examining virtually every square meter of forest floor in his 1 by 2 km dispersion ellipse, mapping every crater position, and the exact location of meteorite fragments associated with each crater. Tsvetkov described Krinov as being more in keeping with a natural historian characteristic of the late 19th century than as a man well versed in modern science. Toward the end of the 1975 expedition, Tsvetkov suggested to Krinov that he remain with a small group of 10 and, instead of continuing the time-consuming method of examining every square meter of the area they instead examine a grid of 25- by 25-m plots with a distance between plots of 200 m. In this way, Tsvetkov felt that he might get a more inclusive determination of the boundary than Krinov had obtainedand earlier cast in concrete by publication.

Sikhote-Alin is a massive fall. The overall size of the meteoroid has been estimated at just under 900,000 kg. Krinov had estimated the post atmospheric mass of the meteoroid at some 70,000 kg. A more recent estimate by Tsvetkov (and others) puts the mass at around 100,000 kg.

The strewn field for this meteorite covered an elliptical area of about 1.3 km². Some of the fragments made craters, the largest of which was about 26 m across and 6 m deep . Fragments of the meteorite were also driven into the surrounding trees as seen in the specimen below.

A ten minute documentary on Sikhote-Alin

Click on images below to enlarge

Sikhote-Alin  Iron, IIAB
Individual embedded in tree branch

Cat Scan Image disk still available - $50

Sikhote-Alin  Iron, IIAB
Individual embedded in tree branch

Sikhote-Alin  Iron, IIAB
Individual embedded in tree branch


Sikhote-Alin  Iron, IIAB
Baby individuals

Sikhote-Alin / Krinov Coin

60 Year Anniversary Coin
2" Diameter zinc alloy
Limited edition of 300



For ordering information please click HERE