A meteor streaked through the sky and exploded Friday over Russia's Ural Mountains with the power of an atomic bomb, its sonic blasts shattering countless windows and injuring more than 950 people.
The spectacle deeply frightened many Russians, with some elderly women declaring that the world was coming to an end. Many of the injured were cut by flying glass as they flocked to windows to see what the source was for such an intense flash of light.
The meteor — estimated to be about 9 tonnes — entered the Earth's atmosphere at a hypersonic speed of at least 54,000 km/h and shattered about 30 to 50 kilometres above the ground, the Russian Academy of Sciences said in a statement.
It released the energy of several kilotons above the Chelyabinsk region, the academy said.
Richard Binzel, a professor of Planetary Science at Massachusetts Institute of Technology, said the meteor was probably about two metres across, or the size of an SUV.
Amateur video broadcast on Russian television showed an object speeding across the sky about 9:20 a.m. local time, just after sunrise, leaving a thick white contrail and an intense flash.
"There was panic. People had no idea what was happening. Everyone was going around to people's houses to check if they were OK," said Sergey Hametov, a resident of Chelyabinsk, a city of 1 million about 1,500 kilometres east of Moscow.
"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.
Saskatoon native Michael Garnett, a goaltender for Traktor Chelyabinsk in the Kontinental Hockey League, told CBC News he was terrified by the noise, which was so loud he was convinced something had happened right next to his building.
"I thought for sure there was an explosion, and then I thought it might have been a natural gas leak or it could have been a bomb or a missile or a plane crash," he said.
Another Chelyabinsk resident, Alexander Yakovets, told CBC News he was woken in his eighth-floor apartment by a "really horrible sound" that he first thought might have been a terrorist attack or a military exercise.
He said he saw a very bright light and heard multiple explosions.
"For a couple of minutes, I thought [the building] was going to fall down," he said.
The explosions broke an estimated 100,000 square metres of glass, city officials said.
A Russian health official said 985 people, including 204 schoolchildren, sought medical care after the explosions with most injured by shards of glass. Athletes at a city sports arena were among those cut up by the flying glass.
It was not immediately clear if any people were struck by space fragments.
Chelyabinsk resident Valya Kazakov said some elderly women in his neighbourhood started crying out that the world was ending.
Injuries on this scale extremely rareCity officials said 3,000 buildings in the city were damaged by the shock wave, including a zinc factory where part of the roof collapsed.
Meteor, meteoroid, or meteorite?Small pieces of space debris — usually parts of comets or asteroids — that are on a collision course with the Earth are called meteoroids. When meteoroids enter the Earth's atmosphere they are called meteors. 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.
The vast implosion of glass windows exposed many residents to the bitter cold as temperatures in the city hovered around – 9 C. The regional governor immediately urged any workers who can pane windows to rush to the area to help out.
Some fragments fell in a reservoir outside the town of Cherbakul, the regional governor's office said, according to the ITAR-Tass.
A six-metre-wide crater was found in the same area, which could come from space fragments striking the ground, the news agency cited military spokesman Yaroslavl Roshchupkin as saying.
Reports conflicted on what exactly happened in the clear skies. A spokeswoman for the Emergency Ministry, Irina Rossius, told the AP there was a meteor shower, but another ministry spokeswoman, Elena Smirnikh, was quoted by the Interfax news agency as saying it was a single meteor.
'A shooting gallery'Meteors typically cause sizeable sonic booms when they enter the atmosphere because they are travelling much faster than the speed of sound. Injuries on the scale reported Friday, however, are extraordinarily rare.
Russian news reports noted that the meteor hit less than a day before the asteroid 2012 DA14 is to make the closest recorded pass of an asteroid — about 28,000 kilometres. CBC reporter Bob McDonald said the asteroid is coming from a different direction than the Russia meteor.
The meteor's shockwave damaged around 3,000 buildings including this zinc factory, where about 600 square metres of the roof collapsed. (Oleg Kargapolov/Chlyabinsk.ru/AP)"We do live in a shooting gallery," McDonald said. "It's one of the hazards of living in a dirty solar system."
McDonald explained that when the space rock "hits the air, it comes to a screeching halt, and the pressure of the air and the heat on the front side of it, compared to the back side, causes the whole thing to collapse in on itself, and it does that so quickly that there's just this massive air burst explosion."
McDonald said the tiny pieces that do make it to the ground will be picked up by people so scientists can determine the exact makeup of the meteorites.
Donald Yeomans, manager of U.S. Near Earth Object Program in California, said it is far too early to provide estimates of the energy released or provide a reliable estimate of the original size.
The site of Friday's spectacular show is about 5,000 kilometres west of Tunguska, which in 1908 was the site of the largest recorded explosion of a space object plunging to Earth. That blast, attributed to a comet or asteroid fragment, is generally estimated to have been about 10 megatons; it levelled some 80 million trees.
Russian politicians reactThe dramatic events prompted an array of reactions from prominent Russians.
A circular hole in the ice of Chebarkul Lake where a meteor reportedly struck near Chelyabinsk. (Associated Press)Prime Minister Dmitry Medvedev, speaking at an economic forum in the Siberian city of Krasnoyarsk, said the meteor could be a symbol for the forum, showing that "not only the economy is vulnerable, but the whole planet."
Vladimir Zhirinovsky, a nationalist leader noted for vehement statements, said "It's not meteors falling. It's the test of a new weapon by the Americans," the RIA Novosti news agency reported.
Deputy Prime Minister Dmitry Rogozin said the incident showed the need for leading world powers to develop a system to intercept objects falling from space.
"At the moment, neither we nor the Americans have such technologies" to shoot down meteors or asteroids, he said, according to the Interfax news agency.
With files from CBC News
發表於 2013-2-15 09:39
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Meteor over Russia1:00
RAW: Meteor blows out school windows1:09