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 almost 1,000 people. The spectacle deeply frightened thousands, with some elderly women declaring the world was coming to an end.
The meteor — estimated to be about 10 tons — entered the Earth's atmosphere at a hypersonic speed of at least 33,000 mph and shattered about 18-32 miles 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.
Amateur videos 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.
The explosions broke an estimated 1 million square feet of glass, city officials said.
Russia's Interfax news agency said close to 1,000 people sought medical care after the explosions and most were injured by shards of glass, according to officials. 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.
"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, about 930 miles east of Moscow, the biggest city in the affected region.
"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.
Amateur videos posted to Youtube showed a bright streaks of light crossing the morning sky. In some videos, a large boom was heard -- possibly an impact or possibly a sonic boom of the meteor sailing through the Earth's atmosphere at more than the speed of sound.
Of note in some of the videos is the remarkable calm with which Russians observed the event. CBS News correspondent Mark Phillips notes that Chelyabinsk is a place where the unusual may actually be taken in stride. It was a major nuclear weapons manufacturing center in the Soviet Union days, with a history of nuclear contamination and evacuations.
At least part of the event was captured on amateur video. Some broadcast on Russian television showed an object speeding across the sky about 9:20 a.m. local time, leaving a thick white contrail and an intense flash.
CBS News contributor Michio Kaku, a physics professor at the City University of New York, says the meteor was a classic example of Mother Nature "showing Hollywood who's boss." He said the meteor was about the size of a house.
The meteor hit less than a day before the asteroid 2012 DA14 is to make the closest recorded pass of an asteroid -- about 17,150 miles. European Space Agency (ESA) spokesman Bernhard Von Weyhein said, however, that there was no connection with the meteor over Russia, it was just a cosmic coincidence.
Professor Kaku told "CBS This Morning," however, that in spite of the ESA's tracing the meteor's trajectory and ruling out a link to 2012 DA14, "asteroids occur in swarms, so it is very possible that (the meteor over Russia) was part of a swarm from it." Kaku said the incident served the residents of Earth with a reminder; that "we are in a cosmic shooting gallery."
Meteors are pieces of space rock, usually from larger comets or asteroids, which enter the Earth's atmosphere. Many are burned up by the heat of the atmosphere, but those that survive and strike the Earth are called meteorites. They often hit the ground at tremendous speed -- up to about 19,000 miles an hour, according to the European Space Agency. That releases a huge amount of force.
Experts say smaller strikes happen five to 10 times a year. Large impacts such as the one Friday in Russia are rarer but still occur about every five years, according to Addi Bischoff, a mineralogist at the University of Muenster in Germany. Most of these strikes happen in uninhabited areas where they don't cause injuries to humans.