February 4, 2004

Being nerds, you'll want to know how I got the odds of being struck by a meteor.

1) The meteor is large enough to make it to the ground without completely burning up.
2) The meteor is not so large that it would have a significant effect on the approximation of 1/2 square meter collision area for a human on Earth.
3) A given meteor has equal odds of hitting anywhere on Earth.

Earth is about 12,000km across. That's a radius of 6x10^6 meters. The surface area of Earth, is 4/3 * PI * r^2 = (roughly) 1.5x10^14. I figure an average human who is standing or sitting will occupy about 1/2 a square meter of the ground. So you occupy about 1 3x10^14th of the Earth's surface. That would mean your odds of getting hit by a given meteor are:

1 in 3x10^14 which is 1 in 300,000,000,000,000 (300 trillion)

Unless, of course, you're from England, in which case that number is read 300 billion. Someday that's going to cause a huge international banking error, I just know it.

Despite those odds, on November 30, 1954, Alabama housewife Ann Hodges was hit by a 3 pound meteor that crashed through the roof of her house. All she got was a bruise.



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