A meteor 15 meters across flared through the skies over Russia's Chelyabinsk region early Friday, triggering an atomic bomb-sized shock wave that injured nearly a thousand people, blew out windows and caused some Russians to fear the end of the world.
It was the largest reported fireball since the Tunguska event in 1908 – an asteroid that flattened millions of trees over a wide area in Siberia – according to NASA's Jet Propulsion Laboratory.
Multiple amateur videos posted online showed the meteor's flaring arc – called a bolide by scientists – as it crossed the western Siberia sky. Others from the scene included the sound of a loud boom, followed by a cacophony of car alarms. One video showed the hurried evacuation of an office building in Chelyabinsk.
"There was panic. People had no idea what was happening. Everyone was going around to people's houses to check if they were OK," Chelyabinsk resident Sergey Hametov told The Associated Press. "We saw a big burst of light then went outside to see what it was and we heard a really loud thundering sound."
Another resident described the meteorite's "flash."
"I was standing at a bus stop, seeing off my girlfriend," Andrei, a local resident who did not give his second name, told Reuters. "Then there was a flash and I saw a trail of smoke across the sky and felt a shock wave that smashed windows."
The fireball's trail, which JPL reported was visible for about 30 seconds and said was "brighter than the sun," lit up one man's morning commute. "I was driving to work, it was quite dark, but it suddenly became as bright as if it was day," Viktor Prokofiev told Reuters. "I felt like I was blinded by headlights."
Estimates of the number of people injured swelled throughout the day, with early reports putting those hurt around 500, with close to 100 people hospitalized. Chelyabinsk health official Marina Moskvicheva later said as many as 985 people had requested medical assistance in the city, many for injuries caused by flying glass. More than 200 children at Chelyabinsk schools, which had just opened, were among the injured, according to officials.
Russia's interior ministry said the shock wave caused the roof of a zinc factory's warehouse to collapse, but that no fatalities were reported.
The fireball entered Earth's atmosphere at 18 km per second, and released hundreds of kilotons of energy, JPL said. The blast's force was the equivalent of the nuclear weapons dropped on Hiroshima and Nagasaki during WWII – many times over.
As many as 10,000 police have been mobilized to aid in recovery and to remove debris from the meteorite, which has been found in three areas around the Chelyabinsk region, according to the ITAR-Tass news agency.
The shallow angle at which the meteor crossed the sky over the city of Chelyabinsk contributed to the amount of damage, releasing energy equivalent to about 300 kilotons of TNT, according to Margaret Campbell-Brown, an astronomer and physicist at the University of Western Ontario.
"It's like a sonic boom," Campbell-Brown said of the rippling shock wave caused by the meteor. "A sonic boom from a plane can shatter windows, but this sonic boom was much stronger than a plane."
The CTBTO, which tracks nuclear disturbances in the Earth's atmosphere, reported that 11 of its 45 infrasound monitoring stations recorded low-frequency sound waves as the meteorite broke up over the Ural mountains a little before 9:30 a.m. local time on Friday.
A photo provided by the Chelyabinsk regional police department showed a 20-foot hole in the ice covering a lake near the town of Chebakul. The local governor's office said in a statement that fragments from the falling meteor had plunged into the lake, according to the Agence France-Presse.
In Russia and around the world, observers marveled at the fireball and its aftermath.
"I went to see what that flash in the sky was about," resident Marat Lobkovsky told the Associated Press. "And then the window glass shattered bouncing back on me. My beard was cut open, but not deep. They patched me up, it's OK now."
Resident Valya Kazakov told the AP that the brilliant flare and sudden explosion caused older women in his neighborhood to fear that the world was ending.
It was a once in a decade event, Dr. Neil deGrasse Tyson, an astrophysicist at the American Museum of Natural History, told TODAY on Friday, saying the impact was the physics equivalent of hitting a brick wall. "When you hit a brick wall, you basically explode, and that's what happened here, and it exploded in midair," Tyson said.
There were no significant disturbances to public utilities or communications, Vladimir Stepanov of the Emergency Situation Ministry told ITAR-Tass. "No serious consequences have been so far recorded," Stepanov said, according to the news agency. "There has been no disruption in the rail and air transport work."