spacetoday.net: Meteor explodes over Russian city

Posted: Fri, Feb 15, 2013, 7:38 PM ET (0038 GMT)
Meteor exploding over Chelyabinsk, Russia

A small asteroid entered the Earth's atmosphere and burst over the Russian city of Chelyabinsk Friday morning, injuring more than 1,000 people and damaging some buildings. The meteor burst at an altitude of 20 to 25 kilometers above the ground at about 10:25 pm EST Thursday (0325 GMT, 9:25 am local time), not far from Chelyabinsk. The blast wave shattered windows and caused other damage to buildings in the city; most of the reported injuries were minor, and no deaths were reported. Scientists believe the meteor was a small stony asteroid, about 15 meters in diameter and weighing about 7,000 tons. The burst had the energy of 300 to perhaps as much as 500 kilotons of TNT. While the burst took place about 16 hours before a slightly larger asteroid, 2012 DA14, passed close to the Earth, scientists said the two events were not related, as the Chelyabinsk meteor entered from a different direction and at a higher velocity. The small object evaded detection because it came in from the direction of the Sun, and thus out of view from telescopes.