The Sikhote-Alin strewn field
The largest iron meteorite shower ever witnessed, which peppered a snowy forest with more than a hundred craters.
Key facts
- Fell
- 12 February 1947, about 10.30 in the morning
- Where
- Sikhote-Alin mountains, Primorye, Russian Far East
- Recovered
- about 23 tonnes
- Field
- an ellipse of about 1.3 square kilometres
- Type
- Iron, IIAB
The fall
An iron meteoroid thought to have weighed around 70 to 100 tonnes before entry blazed across the morning sky, leaving a smoke trail that hung for hours. Its main body broke apart only about 5 to 6 kilometres above the ground, unusually low, so the fragments were still moving fast when they hit.
The ellipse
Because the break-up was so low, the strewn field is compact for so large a fall: an ellipse of about 1.3 square kilometres in steep, wooded hills. Expeditions led by the Soviet Academy of Sciences mapped more than 100 craters and pits, the largest about 26 metres across and 6 metres deep.
Where the big and small pieces landed
Two kinds of piece came down. Individuals separated high up, flew alone and are covered in thumbprint-like regmaglypts. Shrapnel came from masses that shattered on striking frozen ground, leaving twisted, jagged metal. The heaviest single piece, about 1,745 kilograms, is in Moscow. Thousands of small individuals and shards were recovered by metal detector over many seasons.
The law
The fall lies in Russia, which has no law written for meteorites. Expeditions and later private searchers have recovered much material, and Sikhote-Alin is one of the most widely traded irons. Valuable specimens leaving Russia must be declared truthfully to customs.
The full story of Sikhote-Alin
Related pages
Glossary: Strewn field, Strewn field map, Fusion crust, Meteorite ownership