In one sense, the meteor that raced across the morning sky in Chelyabinsk, Russia, was commonplace. Scientists report as much as 80 tons of material fall on Earth from outer space each day. Often, the episodes delight lucky viewers, a “shooting star” nothing more than an asteroid or its remnants or some other object burning up as it travels high in the atmosphere.
Of course, this episode was anything but common. One preliminary calculation put the meteor at 7,000 tons and 50 feet in diameter, hurtling at 40,000 miles per hour. Think of the sonic boom when a jet breaks the sound barrier. Now imagine the building pressure at such a greater speed.
The reality crossed our television screens practically all day on Friday. One scientist explained to the New York Times that the meteor released the equivalent of 300,000 tons or more of TNT, far exceeding the equivalent of 15,000 tons of TNT in the atomic bomb at Hiroshima.
So windows shattered, doors flew open and buildings bent, more than 1,000 people injured, or nothing like it in a 100 years. Yet what may have been most amazing was the coincidence — at the same time, a larger asteroid, long tracked by scientists, making a close pass, about 17,200 miles from Earth, nature sending reminders of its power, and, thankfully, what a small target we are.