By Evan

Ah meteors, the great pieces of rock that fall from the heavens to wreck havoc on the world (rarely). Just a week after a study came out about to confirm the role of a massive impact wiping out the non-avian dinosaurs 66 million years ago, we are reminded that we are not immune to meteors, and they are always a threat. The meteor that exploded above the Russian city of Chelyabinsk caused injuries of over 1000 people, probably caused when people went to their windows to see what had happened, only to find them shattering due to the blast. Russia Today has a great compilation of videos of the blast (I was informed most Russian cars have dashboard cameras to record road rage incidents, which ended up being beneficial to capture some great views of the explosion):

Of course, the big meteoroid related event this weekend was supposed to be about the 2012 DA14, which swung closely by Earth Saturday morning. The always enthusiastic Charley Lineweaver, professor here at RSES, gave an overview of what happened on ABC News Breakfast on Friday Morning.

That wasn’t even it for meteor news. On Saturday, a fairly large “shooting star” was seen over San Franscisco.

Another meteor news story on the weekend was the publication by former RSES visiting fellow Andrew Glickson of the potential discovery of a large, 25 km wide impact crater in South Australia. The study, published in Tectonophysics, analysed the crater using a variety of geophysical techniques, and determined that if it was an impact event, it affected the Earth’s crust to a depth of 6 km. If confirmed, the impact is among the largest ever discovered on the surface of the Earth. The authors also suggested the timing of the impact (360-298 million years ago) make it a compelling possible trigger for a mass extinction event. The existence of shock metamorphosed rock in the area, along with the geophysical anomalies make it a compelling candidate for an impact structure, but they acknowledge a deep seismic reflection survey would be required to confirm that it is indeed an impact structure.

Filtered magnetic intensity data from South Australia, with the potential impact crater marked "Tirrawarra"
Filtered magnetic intensity data from South Australia, with the potential impact crater marked “Tirrawarra 1”

As far as what happened in Russia, we perhaps shouldn’t be treating it as such a rare occurrence. A similar explosion happened over Canada back in 2008, captured here on a police crusier in Edmonton. If this hit over the city, instead of several hundred km to the east, it probably would have had similar results to the one over the weekend.