Chelyabinsk was a massive meteor, stretching across a diameter of 66-feet. In the low winter light of an early morning, its fireball looked apocalyptic as it cut through the sky. For all the destruction, it was not long before witnesses to the event began searching for pieces across the meteor’s massive strewn field. Chelyabinsk was a boom for the meteorite market, its large size and strewn field allowed many pieces of this unique meteor to circulate across the world. Collectors rushed out as soon as they had realized what happened, gathering chunks of space rock from melted holes in the snow and storing the hot stones in their ovens.

The Chelyabinsk meteor is referred to as a bolide, a term for objects which appear like fireballs during entry. The light seen over Chelyabinsk peaked with a magnitude of -27.3, 30 times brighter than the Sun itself. Anyone awake in the early morning would have immediately seen the shift in light, with shadows cast from extreme angles that moved with the arc of the meteor. With its massive diameter, Chelyabinsk is estimated to have weighed over 13,000 tons. At its fastest, it was moving at over 40,000 miles per hour, almost 60 times the speed of sound.

It was after the meteor hit its brightest point that it shattered in a powerful explosion that sent a shockwave of force from the sky. Pieces of the object were flung west of Chelyabinsk, with many meteorites leaving holes in the morning’s snowbanks. Several fragments would eventually be found in Lake Chebarkul, with one weighing up to 1,442 pounds. The impact left a large hole in the lake’s ice which quickly became a pilgrimage site for scientists and meteor hunters who flocked to Chelyabinsk. 

The shock waves from the explosion damaged over 7,000 regional buildings and sent over 1,000 people to the hospital, mostly suffering from lacerations from flying glass. The event was so powerful it created a dust belt in the stratosphere that circled the entire planet and lingered for months. While the event had no reported deaths, it raised some fears over unpreparedness for subsequent meteorites that could menace Earth in the future.

The space around the planet is filled with objects whose orbits cross with Earth, so many in fact, that it is impossible to track them all. Many of these burn up into nothing in the atmosphere, but obviously not all of them. The Chelyabinsk meteor went undetected until its entry, its impact as much a surprise to scientists as the witnesses on the ground. Before this incident, it was thought that such large strikes were a once-in-centuries event. Now, some think it may be a once-in-decades event.

The Chelyabinsk meteorite's geologic makeup classifies it as a chondrite—a stony meteorite full of round mineral grains. These meteorites are made up of iron oxides and silicates that originated from a larger body in the asteroid belt. The dark black outer layer of the meteorite is a relatively new addition though; it was created during the entry to Earth's atmosphere. This outer coating is what is known as a fusion crust. When the Chelyabinsk meteorite rocketed to the ground, the high speed and air friction caused its exterior to rapidly heat up. A thin layer of material melted and quickly cooled, turning into a dark and glassy coating.

Fortunately, the Chelyabinsk meteorite exploded in midair, lessening the potential damage of the impact. If you are wondering what it may have been like had the meteorite failed to airburst or if it had been even larger, then check out this detailed simulator of meteorite impacts created by Neal Agarwal!