A meteor that exploded over the Bering Sea in December released 10 times the energy of an atomic bomb into the atmosphere.
The asteroid, which was about 10 meters wide, disintegrated in the skies off the coast of Russia’s Kamchatka peninsula on December 18. It unleashed 173 kilotons of energy, making it the second-biggest fireball in recent decades next to the 440-kiloton meteor that rocked the Russian city of Chelyabinsk on February 15, 2013.
Unlike the Chelyabinsk event, the Bering Sea fireball did not make a big news splash after it impacted because it occurred over a remote and unpopulated area. Chelyabinsk, in contrast, is home to more than one million people, many of whom witnessed or were injured by the explosion. Some even captured the dazzling airburst on camera, which instantly enabled viewers around the world to share the sight of the blast.
The Bering Sea meteor was initially detected by US Air Force satellites, as well as decades-old infrasound stations that are designed to flag potential nuclear detonations, according to New Scientist. NASA’s Center for Near Earth Object Studies (CNEOS), which tracks hazardous objects near our planet, logged the airburst on its map of fireballs.
Word of the fireball began to spread after Peter Brown, a meteor specialist at Western University in Canada, tweeted about the infrasound detections of the airburst on March 8.
Brown pointed out that extremely energetic impacts like this occur once every few decades on average.
Scientists have made huge strides in tracking potentially hazardous Near Earth Objects (NEOs) in recent decades, but both the Bering Sea and Chelyabinsk meteors remained off the grid until they exploded.
Fortunately, most space rocks that collide with Earth burn up in the atmosphere and only produce a small amount of debris that reaches the ground (such as the Chelyabinsk meteorite).
But even when these objects explode at high altitudes, the resulting airbursts can deal significant damage. The shockwave and flash from Chelyabinsk meteor caused injuries such as temporary blindness and wounds from shattered glass and collapsing structures. But even that meteor has nothing on the most energetic airburst on record—the Tunguska event of June 1908.
That blast is estimated to have released 10 to 15 megatons of energy, flattening hundreds of square miles of forest around the Podkamennaya Tunguska river in Siberia. There were no confirmed deaths, but the specter of such a massive airburst is one reason why scientists continue to develop better observatories for tracking and cataloguing potentially dangerous space rocks.
After all, if the Bering Sea meteor had exploded over a more populated area, it might have caused real damage and attracted much more immediate attention than it did.
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