These meteorites are approximately 4.5 billion years old. It would have broken off from it's parent body about 320 million years ago then entered the Earth's atmosphere on the 12th February 1947.
The Sikhote-Alin meteorite is primarily an iron meteorite, composed of approximately 93% iron and 5.9% nickel. It also contains smaller amounts of cobalt, phosphorus, sulphur, germanium, and iridium. Structurally, it's classified as a coarse octahedrite, belonging to the IIAB group of iron meteorites.
These pieces feature regmaglypts—thumbprint-like indentations—on the surface of each specimen. Regmaglypts are shallow dimples or depressions that develop on the surface of some meteorites as they travel through Earth’s atmosphere. They are thought to form when small vortices of hot gas, carrying droplets of molten metal, swirl across the surface and erode it in localized areas.
Dimensions
This meteorite is 151g and at the widest part is 51mm.
Meteorites
Iron meteorites are space rocks made mostly of iron with a bit of nickel mixed in. When they fall through Earth’s atmosphere, they often form a thin black crust that can rust over time. Even though only around 5% of seen meteorite falls are iron, they’re easier to spot and survive much longer in the ground than other types—so they’re found more often than stony or stony-iron meteorites
When space rocks—called meteors—make it all the way to the ground, they’re then known as meteorites.
About the Sikhote Alin Meteor Shower
On the 12th February 1947, a great fireball exploded over Eastern Siberia, scattering these iron fragments over one and a half square kilometres. There were over 200 impact holes with the largest recorded as 26 meters across.
Sikhote Alin is one of the most spectacular falls of recorded history and the largest of a very small number of recent iron meteorite falls.
On November 20, 1957, the Soviet Union released a stamp commemorating the 10th anniversary of the Sikhote-Alin meteorite shower. The design features a painting by Soviet artist P. I. Medvedev, who witnessed the event firsthand—he was sitting by his window, beginning a sketch, when the fireball streaked across the sky, prompting him to immediately start drawing the scene.
