The Chelyabinsk “superbolide” exploded over Russia at 9.20am on 15th February 2013, causing extensive damage and making news headlines across the globe.Huge amounts of extraterrestrial material were collected on the ground in the days that followed this massive explosion. This debris is officially classified as being from the Chelyabinsk meteorite, and has the composition of an LL5 ordinary chondrite.
The debris and vapour trail left after the explosion of the Chelyabinsk “superbolide” Image: Alex Alishevskikh/Wikipedia
But what does this material look like? Well now we have samples of the Chelyabinsk meteorite in our outreach collection. These consist of a 41g partly fusion-crusted stone and five small so-called Chelyabinsk “peas”.
The new Chelyabinsk samples (image: Richard Greenwood)
As can be seen from the image above, the larger stone is highly fractured with dark shock melt veins cutting across the specimen. These did not form as a result of the Chelyabinsk explosion, but are due to much earlier events. A recent paper by Righter et al (2015) suggests that Chelyabinsk shows evidence of up to eight distinct collisional events, ranging in age from 4.53 billion to 27 million years ago.The tiny “peas” are representative of much of the debris from the explosion, which resulted in massive scale fragmentation of the incoming meteoroid.