Updated at 9:34 a.m. MOSCOW 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. A large meteor streaks across the sky of Russia's Ural Mountains region, Feb. 15, 2012. / AP/Nasha Gazeta 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. Fragments of giant meteor injure 500 in Russia 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. 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."