Russia wasn’t the only country rattled by the meteor that exploded over Chelyabinsk on Feb. 15.
According to the Comprehensive Test Ban Treaty Organization (CTBTO), the blast produced the largest low-frequency sound wave ever picked up by its nuclear test monitoring system. The 32-second-long sound wave traveled as far as Antarctica and Greenland, boasting 450-500 kilotons of energy — making it about as powerful as 30 nuclear bombs. People cannot hear them, however, according to the CTBTO.
“It’s not a single explosion, it’s burning, traveling faster than the speed of sound,” the international agency said in a news release. “That’s how we distinguish it from mining blasts or volcanic eruptions.”
(WATCH: Meteorites Crash in Russia)
Margaret Campbell-Brown, astronomer at the University of Western Ontario in Canada, told CNN that the size of the wave is helping scientists determine how big the meteor was. Then they’ll be able measure the flaming space rock using “an estimate of the meteor’s speed from the numerous dashboard and mobile-phone cameras that captured the scene.” Current estimates say the Russian meteor had a width of 56 feet, weighed 7,000 tons and was traveling at 40,000 mph, according to CNN.
Brown told CNN, “In terms of [meteors] we have observed, this is the largest since Tunguska” — the object that exploded over a remote Siberian forest in 1908, annihilating 80 million trees across some 830 square miles.
More than 1,500 people were injured by wayward glass shards when the Chelyabinsk meteor broke up in mid-air earlier this month.
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