Lots of interesting information at and through this link:

http://www.washingtonpost.com/blogs/capi...d7adb_blog.html

"...meteors this big enter Earth’s atmosphere about every 5 years, but that the impact of this particular meteor on humans is “unprecedented” in modern times. A news article in the journal Nature says it’s the biggest recorded object to hit Earth in a century.

"Both because most of the Earth’s land area is not densely populated and oceans cover such a large area, most inbound space material is not observed and eludes human impact."


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