Scientists studying the shock wave from a meteor that passed over Russia in February say it was so powerful that it travelled twice around the earth.
The study, which has appeared in the science journal Geophysical Research Letters, included data from the International Monitoring System (IMS) network operated by the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO).
Researchers used sensors normally deployed to detect evidence of nuclear tests to gather evidence of what they describe as 'the most powerful event ever recorded' by the system.
Around 1,000 people were hurt when the 10,000 tonne space rock burned up above Russia.
Alexis Le Pichon, from the Atomic Energy Commission in France and colleagues report that the explosive energy of the impact was equivalent to 460 kilotons of TNT.