Historic Russian Meteorite Fall
The largest meteorite to light up Earth’s sky in more than a century exploded above Russia’s Ural Mountains on February 15 at 9am. The first sign was when the sky brightened dramatically in the direction of the rising sun. Within seconds, that glare became blinding. 3 minutes after the initial fireball appeared in the sky, a massive shock wave hit Chelyabinsk, shattering over 100,000 windows. Thankfully, no one was killed, but 1,500 people sought medical attention – most of them injured from flying glass. The altitude of the explosion was about 23,300 meters above ground, and the meteor was moving at a velocity of 18.6km/s. The force radiated by the main fireball reached about 90 kilotons. In comparison, the atomic bomb detonated above Hiroshima in 1945, was roughly 15 kilotons. NASA scientists estimated that the total energy delivered during the entire entry was at 500 kilotons. In order to deliver that amount of energy, the incoming object would needed to be 17m in diameter with a mass of 10,000 tons. A small asteroid!
The last major meteorite impact was in 1908 above the Tunguska region, south-central Siberia, and it flattened some 2,000 sq. km of forest, releasing between 30 megatons of energy.