Here's a link that summarizes what we know about the meteor that exploded over Russia, injuring over 1000 people. The meteor was around 15 feet across, moving 40,000 miles per hour, and exploded at least 6 miles above the ground. (Have the terms meteor and meteorite ever been misused more often? Meteors are only meteors until the instant they touch the earth, whereupon they become meteorites.)

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There are also several links over on the right to Science News articles as they are posted.