The asteroid that tore through the skies over central Russia in February, injuring more than 1,200 people, had a more powerful impact than scientists originally assessed, new studies released on Wednesday showed.
The research also raised the prospect that objects the size of the 19m Chelyabinsk asteroid in orbits near Earth are more common than current estimates, perhaps numbering as high as 20 million.
“Chelyabinsk was an eye-opener, but we shouldn’t give it an excessive amount of importance as to what may come in the future,” said Bill Cooke, head of NASA’s Meteoroid Environment Office at the Marshall Space Flight Center in Huntsville, Alabama.
“A lot is going to depend on where an event occurs ... The odds are an event will occur over the ocean rather than over a populated area,” Cooke said in a conference call with reporters.
Shock waves from the asteroid’s Feb. 15 explosion about 30km above the heavily populated Russian city of Chelyabinsk were powerful enough to knock people off their feet, the new studies showed.
At its peak, the fireball was about 30 times brighter than the sun and pumped out enough ultraviolet radiation to cause instant sunburns, researchers said in a trio of papers published this week.
The explosion over Chelyabinsk was as powerful as about 500 kilotons of TNT — more than 30 times the force of the Hiroshima nuclear bomb, the studies showed.
Debris from shattered windows and damaged buildings sent more than 1,200 people to hospitals for treatment.
Researchers collected hundreds of cellphone, dashboard and security camera videos of the event to reconstruct the asteroid’s flight path, speed and midair explosion.
Teams also analyzed rocks and fragments recovered from the ground and determined that the asteroid had been flying solo for a relatively short 1.2 million years.
Scientists suspect it was once part of a larger body that was torn apart by Earth’s gravity during a previous flyby.
“Perhaps 1.2 million years ago, we already had a close encounter with the Chelyabinsk meteoroid, at which time the rock split in two and this object went on its course, only to hit us now very recently,” Peter Jenniskens, with NASA’s Ames Research Center in Mountain View, California, said in an interview with Science magazine.
The new analysis, pieced together from hundreds of video clips, shows the asteroid entered Earth’s atmosphere at the blistering speed of about 19km per second, slightly faster than previously reported.
A related analysis shows that current computer models underestimate the amount of energy released by fast-moving Chelyabinsk-type asteroids that break apart in midair.
So far, telescopic surveys have found only about 500 similarly sized objects in orbits that pass close to Earth, but that population may be as high as 20 million, Peter Brown, with the University of Western Ontario, reported in a related study.
A trio of papers on the Chelyabinsk fireball was published in the journals Nature and Science this week.
Chinese President Xi Jinping (習近平) is to visit Russia next month for a summit of the BRICS bloc of developing economies, Chinese Minister of Foreign Affairs Wang Yi (王毅) said on Thursday, a move that comes as Moscow and Beijing seek to counter the West’s global influence. Xi’s visit to Russia would be his second since the Kremlin sent troops into Ukraine in February 2022. China claims to take a neutral position in the conflict, but it has backed the Kremlin’s contentions that Russia’s action was provoked by the West, and it continues to supply key components needed by Moscow for
Japan scrambled fighter jets after Russian aircraft flew around the archipelago for the first time in five years, Tokyo said yesterday. From Thursday morning to afternoon, the Russian Tu-142 aircraft flew from the sea between Japan and South Korea toward the southern Okinawa region, the Japanese Ministry of Defense said in a statement. They then traveled north over the Pacific Ocean and finished their journey off the northern island of Hokkaido, it added. The planes did not enter Japanese airspace, but flew over an area subject to a territorial dispute between Japan and Russia, a ministry official said. “In response, we mobilized Air Self-Defense
CRITICISM: ‘One has to choose the lesser of two evils,’ Pope Francis said, as he criticized Trump’s anti-immigrant policies and Harris’ pro-choice position Pope Francis on Friday accused both former US president Donald Trump and US Vice President Kamala Harris of being “against life” as he returned to Rome from a 12-day tour of the Asia-Pacific region. The 87-year-old pontiff’s comments on the US presidential hopefuls came as he defied health concerns to connect with believers from the jungle of Papua New Guinea to the skyscrapers of Singapore. It was Francis’ longest trip in duration and distance since becoming head of the world’s nearly 1.4 billion Roman Catholics more than 11 years ago. Despite the marathon visit, he held a long and spirited
The pitch is a classic: A young celebrity with no climbing experience spends a year in hard training and scales Mount Everest, succeeding against some — if not all — odds. French YouTuber Ines Benazzouz, known as Inoxtag, brought the story to life with a two-hour-plus documentary about his year preparing for the ultimate challenge. The film, titled Kaizen, proved a smash hit on its release last weekend. Young fans queued around the block to get into a preview screening in Paris, with Inoxtag’s management on Monday saying the film had smashed the box office record for a special cinema