Recent witnessed falls in Sariçiçek, Turkey 2015 and Chelyabinsk, Russia in 2013. Both were caught on video as they crashed into buildings. Jupiter is throwing rocks at us again. 🙂
These falls often have several smaller individual pieces like this, where an airburst of the inbound asteroid makes it a shotgun blast, as was documented in Chelyabinsk. Little reminders that we need a space program… and there has never been a better time (thanks to Moore’s Law and B612).
• Left: 55g Individual Bingol Sariçiçek — Howardite
The Sariçiçek (Bingöl) meteorite was observed as a bright bolide late on the night of September 2, 2015 over Sarçiçek Village, in Turkey. Soon after the meteor was seen, meteorites were heard hitting houses in the village of Sariçiçek. The next day small meteorites were found on the street and yards.
Howardites are the H of the HED group meteorites which may originate from asteroid 4 Vesta. Like many of the achondrite meteorites, Howardites have a very distinctive and beautiful glassy fusion crust with flow lines (in contrast to the matt-black of Chelyabinsk) and are among the rarest of the meteorite types.
In this case, thanks to data brought back by the DAWN spacecraft and NASA analysis, we know this rock was dislodged 22 million years ago from the U-shaped Antonia impact crater on asteroid 4Vesta. Noble gas studies showed that the terrain surface where the collision happened was covered in howardite material like Sariçiçek prior to this collision, and was refreshed by impacts or landslides 13 million years earlier.
• Right: 37g Individual Chelyabinsk — LL5 Shock Melt Breccia
The Chelyabinsk meteor was a superbolide that entered Earth’s atmosphere over Russia on 15 February 2013. It was caused by an approximately 20 m near-Earth asteroid with a speed of 19 kilometres per second (42,500 MPH). It quickly became a brilliant superbolide meteor over the southern Ural region, damaging 7,200 buildings and injuring 1,613 people.
The bulk of the object’s energy was absorbed by the atmosphere, with a total kinetic energy before atmospheric impact estimated from infrasound and seismic measurements to be equivalent to the blast yield of 400–500 kilotons of TNT, or 26 to 33 times as much energy as that released from the atomic bomb detonated at Hiroshima.
The Chelyabinsk meteor originated in the asteroid belt between Mars and Jupiter. It has veins of black material which had experienced high-pressure shock and were once partly melted, due to a previous collision. The metamorphism in the chondrules in the meteorite samples indicates the rock making up the meteor had a history of collisions and was once several kilometres below the surface of a much larger LL-chondrite asteroid.
Leave a Reply