MOSCOW — With a blinding flash and a booming shock wave, a meteor blazed across the western Siberian sky Friday and exploded with the force of 20 atomic bombs, injuring more than 1,000 people as it blasted out windows and spread panic in a city of 1 million.
While NASA estimated the meteor was only about the size of a bus and weighed an estimated 7,000 tons, the fireball it produced was dramatic. Video shot by startled residents of the city of Chelyabinsk showed its streaming contrails as it arced toward the horizon just after sunrise, looking like something from a world-ending science-fiction movie.
The largest recorded meteor strike in more than a century occurred hours before a 150-foot asteroid passed within about 17,000 miles of Earth. The European Space Agency said its experts had determined there was no connection between the asteroid and the Russian meteor — just cosmic coincidence.
The meteor above western Siberia entered the Earth’s atmosphere about 9:20 a.m. local time at a hypersonic speed of at least 33,000 mph and shattered into pieces about 18 to 32 miles high, the Russian Academy of Sciences said. NASA estimated its speed at about 40,000 mph, said it exploded about 12 to 15 miles high, released 300 to 500 kilotons of energy and left a trail 300 miles long.
“There was panic. People had no idea what was happening,” said Sergey Hametov of Chelyabinsk, about 930 miles east of Moscow in the Ural Mountains.
“We saw a big burst of light, then went outside to see what it was and we heard a really loud, thundering sound,” he told The Associated Press by telephone.
The shock wave blew in more than 1 million square feet of glass, according to city officials, who said 3,000 buildings in Chelyabinsk were damaged. At a zinc factory, part of the roof collapsed.
The Interior Ministry said about 1,100 people sought medical care after the shock wave and 48 were hospitalized. Most of the injuries were caused by flying glass, officials said.
Scientists estimated the meteor unleashed a force 20 times more powerful than the Hiroshima bomb, although the space rock exploded at a much higher altitude. Amy Mainzer, a scientist at NASA’s Jet Propulsion Laboratory, said the atmosphere acted as a shield.
The shock wave may have shattered windows, but “the atmosphere absorbed the vast majority of that energy,” she said.
Emergency Situations Ministry spokesman Vladimir Purgin said many of the injured were cut as they flocked to windows to see what caused the intense flash of light, which momentarily was brighter than the sun.
There was no immediate word on any deaths or anyone struck by space fragments.
Some meteorite fragments fell in a reservoir outside the town of Chebarkul, the regional Interior Ministry office said. The crash left a 26-foot crater in the ice.
Meteors typically cause sizeable sonic booms when they enter the atmosphere because they are traveling so much faster than the speed of sound. Injuries on the scale reported Friday, however, are extraordinarily rare.
“I went to see what that flash in the sky was about,” recalled resident Marat Lobkovsky. “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.”
The many broken windows exposed residents to the bitter cold as temperatures in the city were expected to plummet to minus 4 Fahrenheit overnight. The regional governor put out a call for any workers who knew how to repair windows.
Meteroids are small pieces of space debris — usually parts of comets or asteroids — that are on a collision course with the Earth. They become meteors when they enter the Earth’s atmosphere. Most meteors burn up in the atmosphere, but if they survive the frictional heating and strike the surface of the Earth they are called meteorites.
NASA said the Russian fireball was the largest reported since 1908, when a meteor hit Tunguska, Siberia, and flattened an estimated 80 million trees. Chelyabinsk is about 3,000 miles west of Tunguska. The Tunguska blast, attributed to a comet or asteroid fragment, is generally estimated to have been about 10 megatons.