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Name: Kevin
Status: other
Grade: other
Country: USA
Date: Spring 2012

Why was the meteor, weighing 150,000 lbs and the size of a mini van that landed recently in California, not detected before it reached Earth? I had thought I read we were able to detect meteors somewhere around three years out prior to entering Earth's atmosphere.

Dear Kevin,

Good question. We can detect larger asteroids, half a kilometer or larger, before they threaten us, but rarely smaller objects. This object is much smaller.

Sincerely David Levy

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