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careysub
Carpal Tunnel

Reged: 02/18/11

Loc: Rancho Cucamonga, CA
Lifetime Average Distance to a Meteorite Fall
#5700147 - 02/25/13 04:11 PM

After examining the data on meteorite fall rates I calculate that on average during your whole life (80 years) you will be within 4.3 miles of one meteorite with a mass of a gram or greater hitting the ground (distance uncertainty is 40%).

The City of Los Angeles gets hit once per decade.

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Mister T
Pooh-Bah

Reged: 02/01/08

Loc: Upstate NY
Re: Lifetime Average Distance to a Meteorite Fall [Re: careysub]
#5700544 - 02/25/13 08:47 PM

Can you tell me in which direction to search?

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csa/montana
Den Mama

Reged: 05/14/05

Loc: montana
Re: Lifetime Average Distance to a Meteorite Fall [Re: careysub]
#5701205 - 02/26/13 09:10 AM

Quote:

After examining the data on meteorite fall rates I calculate that on average during your whole life (80 years) you will be within 4.3 miles of one meteorite with a mass of a gram or greater hitting the ground (distance uncertainty is 40%).

The City of Los Angeles gets hit once per decade.

Montana has only 6 recorded falls, so I think I may be an exception to your data.

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careysub
Carpal Tunnel

Reged: 02/18/11

Loc: Rancho Cucamonga, CA
Re: Lifetime Average Distance to a Meteorite Fall [Re: csa/montana]
#5703314 - 02/27/13 11:28 AM

Multiple sources of data have provided a good mathematical model of the meteor flux vs meteor size.

The meteorites that do fall are very rarely observed.

The frequency is heavily weighted toward the lower end cut-off (1 gram) and a rock weighing a few grams falling from the sky falls no faster than a rock tossed from a building. Even in the middle of city rarely would anyone notice it, or think much about it if they did.

Recorded falls are usually of the much larger, much rarer sort (and most of these are missed as well). How many falls in the low gram (for the total mass of the meteorite, we aren't talking fragments of a larger one) are ever recorded, despite being by far the most frequent?

If I run across a list of recorded falls in some specific area, with their weight, I can take a crack at calculating their detection rate (there may be such a study out there already).

It is interesting knowing about this slow drizzle of little meteors though. Hard to catch them in the act unfortunately.

But it does indicate how quickly they will accumulate on a surface where there normally would be no rocks at all (ice sheets, salt flats, sand plains, etc.) where most meteorites are identified these days.

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Dick Lipke
professor emeritus

Reged: 02/20/07

Loc: Marine City,Mich.
Re: Lifetime Average Distance to a Meteorite Fall [Re: careysub]
#5703823 - 02/27/13 04:41 PM

Quote:

Multiple sources of data have provided a good mathematical model of the meteor flux vs meteor size.

The meteorites that do fall are very rarely observed.

The frequency is heavily weighted toward the lower end cut-off (1 gram) and a rock weighing a few grams falling from the sky falls no faster than a rock tossed from a building. Even in the middle of city rarely would anyone notice it, or think much about it if they did.

Recorded falls are usually of the much larger, much rarer sort (and most of these are missed as well). How many falls in the low gram (for the total mass of the meteorite, we aren't talking fragments of a larger one) are ever recorded, despite being by far the most frequent?

If I run across a list of recorded falls in some specific area, with their weight, I can take a crack at calculating their detection rate (there may be such a study out there already).

It is interesting knowing about this slow drizzle of little meteors though. Hard to catch them in the act unfortunately.

But it does indicate how quickly they will accumulate on a surface where there normally would be no rocks at all (ice sheets, salt flats, sand plains, etc.) where most meteorites are identified these days.

Speaking of ice sheets, ~400 specimens

www.psrd.hawaii.edu/CosmoSparks/Feb13/ANSMETprogram.html

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skinnyonce
super member

Reged: 03/23/11

Loc: ohio
Re: Lifetime Average Distance to a Meteorite Fall [Re: Dick Lipke]
#5704434 - 02/27/13 10:29 PM

So not all the weird noises I hear are from squirrels on the roof

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Glassthrower
Vendor - Galactic Stone & Ironworks

Reged: 04/07/05

Loc: Oort Cloud 9
Re: Lifetime Average Distance to a Meteorite Fall [Re: skinnyonce]
#5704656 - 02/28/13 01:39 AM

I'm never more than 10-feet from a meteorite in the house, and I carry a small one in my pocket. So I am never far from one.

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careysub
Carpal Tunnel

Reged: 02/18/11

Loc: Rancho Cucamonga, CA
Re: Lifetime Average Distance to a Meteorite Fall [Re: Glassthrower]
#5704869 - 02/28/13 08:25 AM

If you drop a specimen, I guess you could call that a "fall". (The unfortunate collector on the adjacent thread has many to his recent credit.)

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