2013-02-15. Impact event over Russia's Southern Ural Mountains

posted Feb 18, 2013, 12:20 PM by Alan Gould
 at 3:20:26 UTC (9:20 AM local time in Chelyabinsk, Russia). Dome-L Planetarians listserv. The meteor moved from East to West. It was also observed from Tyumen, Ekaterinaburg, and Northern Kazakhstan. Reports that a few fragments have been recovered ~80 km west of Chelyabinsk (near a village called Satka). Based on infrasound reports (9 stations reporting, one as far away as Alaska), the event lasted 32.5 seconds, corresponding to an equivalent yield of 470 kT TNT (which, in turn, equates to a size of ~17 meters; which, in turn, equates to a mass of ~10,000 metric tons). Velocity of impact: ~18 km/s (~40,000 mph). Largest reported fireball since Tunguska impact (1908 Jun 30). 1200+ people injured [no reported deaths] mostly from shattered glass. Blast wave damaged 3000+ structures (shallow graze, probably ~20 deg elevation; airburst and subsequent shockwaves from explosion). Why didn't we see it coming? (1) It came at us from 'out of the Sun'.  (2) Small objects like this (just under 20 meters) would likely be fainter than 25th mag--below our capability to detect right now. Compilation of videos: http://zyalt.livejournal.com/722930.html There is no relation to the close approach of asteroid 2012 DA14 (same day, 15 Feb) as DA14 was on a South-to-North path over the Earth. [To see photos and videos of Asteroid 2012 DA14, visit Universe Today.]