Researchers say the shock wave from the meteor that exploded over Russia's Ural Mountains in February was so powerful that it traveled twice around the globe.
More than 1,200 people were injured when the 17-meter-across, 10,000-ton meteor burned up above Chelyabinsk.
According to a study
published in the journal "Geophysical Research Letters," scientists studied data from the International Monitoring System network of sensors.
They can detect large blasts from nuclear tests and other sources.
The researchers report the explosive energy was equivalent to 460 kilotons of TNT, making it the most energetic event reported since the 1908 Tunguska meteor in Siberia, which flattened trees across 2,000 square kilometers of forest.
The atomic bomb dropped on Hiroshima was the equivalent of 16 kilotons of TNT.
Based on reporting by BBC and RFE/RL