Following last week's meteorite explosion, scientists have finally had a chance to sit down and figure out exactly what happened — and the results help explain why it shook Russia so hard.
Peter Brown, from the University of Western Ontario, Canada, has been using the extremely low-frequency sound waves detected during the incident to work out exactly what happened. The ESA explains:
The object is estimated to have been about 17 m across with a mass of 7,000–10,000 tonnes when it hit atmosphere. It exploded with a force of nearly 500 kilotons of TNT –- some 30 times the energy released by the Hiroshima atomic bomb — around 15 to 20 km above the ground.
No wonder reports from Chelyabinsk, the city close to where the meteorite struck, described widespread window breakages and structural damage. [ESA]