[meteorite-list] Experts Skeptical of Peruvian Meteorite Impact

From: Chris Peterson <clp_at_meteoritecentral.com>
Date: Thu, 20 Sep 2007 22:10:54 -0600
Message-ID: <03ed01c7fc05$6fb3d140$0a01a8c0_at_bellatrix>

The point is that we aren't talking about an ordinary meteorite, but a
meteorite that arrives at the ground retaining a hypersonic speed.
That's easier for an iron, because it can potentially survive much
deeper into the atmosphere without being disrupted. I only know of one
documented small crater forming event, and that's Sikhote-Alin (anybody
know of others? Maybe Cali almost qualifies?) Had that body been stony,
it certainly would not have produced any craters, since it would have
shattered much higher and the resulting meteorites would have landed at
low speeds. So I'd argue that a reasonable case could be made that small
crater forming events are going to be weighted towards iron bodies, even
though irons themselves represent only a few percent of falls.

Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com


----- Original Message -----
From: "Jason Utas" <meteoritekid at gmail.com>
To: "Chris Peterson" <clp at alumni.caltech.edu>; "Meteorite-list"
<meteorite-list at meteoritecentral.com>; "Sterling K. Webb"
<sterling_k_webb at sbcglobal.net>
Sent: Thursday, September 20, 2007 6:20 PM
Subject: Re: [meteorite-list] Experts Skeptical of Peruvian Meteorite
Impact


>> Maybe he meant (or said, and was misreported) that a small crater
>> forming
>> event was much more likely to involve an iron parent? That might be a
>> reasonable statement.
>
> Given that any given falling meteorite is ~950% more likely to be a
> stone than an iron, I don't see this as likely...
>
> With regards to the smaller likelihood of such a small crater being
> produced by a stone rather than an iron (Sterling), I would have to
> say that without some comparisons as to the relative abundances of
> such stony bodies to irons, and without knowing any information such
> as entry angle or velocity, not to mention the fact that without such
> data, we don't even know what size the body initially was to any
> reasonable degree, I would conclude that any such statement would have
> had to have been made -very- prematurely.
>
> Jason
Received on Fri 21 Sep 2007 12:10:54 AM PDT