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On December 18, 2018, one of the most powerful known explosions of a meteor for more than a century shook the atmosphere over the Bering Sea. According to estimates, the 32-foot-wide rock was moving at a speed greater than 71,000 miles at the time when it triggered an explosion equivalent to 73 kilotons of TNT, more than 10 times the power of the atomic bomb of Hiroshima.
Incredibly, because of the altitude at which the explosion occurred (16 miles) and its remote location, astronomers following the meteors only learned of it three months later.
"It's an unusual event," Peter Brown, a meteorologist and professor of physics and astronomy at Western University in Ontario, Canada, told the CBC. "We do not see things that big so often."
Although no one below seems to have witnessed the huge fireball, NASA's Terra satellite, observing Earth, was in first place. According to the space agency, no less than five of Terra's nine multi-angle spectro-radiographic imaging (MISR) cameras captured the fiery end of the meteor.
"The shadow of the trace of the meteor through the Earth's atmosphere, projected on the top of the clouds and elongated under the angle of the low sun, is northwest," they write. . "The orange cloud left by the fireball overheating the airflow is visible below and to the right of the GIF center."
The MISR instrument, also on Terra, also saw the great "fireball" – the term used for exceptionally bright meteors – visible over a large area – as it exploded – about 16 km above the Bering Sea, far enough to pose no danger. pic.twitter.com/lyjyZKBZOm
– NASA Earth (@NASAEarth) March 22, 2019
A true color image, captured by Terra's medium-resolution Modis (SpectroRadiometer Imaging Resolution SpectroRadiometer) instrument, has also been published, showing the trace of the meteor and its explosion.
A true color image of the meteor that exploded over the Bering Sea on December 18, captured by Terra's MODIS instrument. (Photo: NASA / GSFC / LaRC / JPL-Caltech, MISR Team)
According to NASA, the explosion associated with this fireball is the largest observed since the Chelyabinsk event on Russia in 2013 and probably the third most important since the Tunguska event in 1908. Nevertheless, despite its unusual size, the agency recalled that such heavenly bombardments of the Earth are not uncommon. By 2019, the National Meteor Foundation had recorded 154 Fireball events.
"The public should not be worried," said Paul Chodas, director of NASA's Center for Near-Earth Objects Research at JPL. "Because these events are normal, asteroids have a constant impact on the Earth, even though they are usually much smaller than this size."
In connection with MNN:
NASA captures a huge explosion of meteorites over the Bering Sea
The 32-foot-wide meteor over the Bering Sea would have exploded with a power 10 times greater than that of the atomic bomb of Hiroshima.
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