At least these were the initial NASA estimations made public to the press Friday afternoon. Hours later NASA revised these figures and explained it is now believed the meteor’s size was larger than initially estimated.
According to the new data NASA explains that the 17 meters wide meteor that weighed ten thousand tons was travelling at a speed of 64300km/h when it exploded and generated a blast equivalent of a 500 kiloton explosion.
Another unrelated event was the fireball that was spotted over California in the San Francisco Bay Area. As with the Russian meteor explosion here as well the sky was lit because of an explosion but the fireball had little other effect and no damage or injury was reported. NASA explains these meteor events are normal to happen from once in a while. However in case of the Russian Meteor explosion NASA commented that having a meteor of this size is indeed rare that would normally happen only once every hundred years. The last such major meteor event happened in 1908 in Russia when a space rock exploded over the Tunguska River and destroyed 2137 square km of forest land.