MOSCOW (AP) - 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.
A meteorite contrail is seen over a village near Chelyabinsk, Russia, Friday.
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 900 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 said.
The shock wave blew out an estimated 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.
Some meteorite fragments fell in a reservoir outside the town of Chebarkul. The crash left a 25-foot crater in the ice.
The 150-foot space rock that safely hurtled past Earth at 2:25 p.m. EST Friday was dubbed Asteroid 2012 DA14 and was discovered a year ago. It came closer than many communication and weather satellites that orbit 22,300 miles up.
The asteroid was invisible to astronomers in the United States at the time of its closest approach on the opposite of the world. But in Australia, astronomers used binoculars and telescopes to watch the point of light speed across the clear night sky.
Jim Green, NASA's director of planetary science, called the back-to-back celestial events an amazing display.
"This is indeed very rare and it is historic," he said on NASA TV. "These fireballs happen about once a day or so, but we just don't see them because many of them fall over the ocean or in remote areas. "
Experts said the Russian meteor could have produced much more serious problems in the area hosting nuclear and chemical weapons disposal facilities.
Vladimir Chuprov of Greenpeace Russia noted that the meteor struck only 60 miles from the Mayak nuclear storage and disposal facility, which holds dozens of tons of weapons-grade plutonium.