[meteorite-list] Re: New Naklha Dog Evidence

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:55:51 2004
Message-ID: <200201260152.RAA21931_at_zagami.jpl.nasa.gov>

>
> The quote describing the circumstances of the fall contains a datum which is testable and
> could yield information:
>
> "The fearful column which appeared in the sky at Denshal
> was substantial. The terrific noise it emitted was an
> explosion which made it erupt in several fragments of
> volcanic materials. These curious fragments, falling to earth
> buried themselves into the sand to the depth of about one metre."
>
> Someone somewhere with more specific engineering experience ought to be able to tell us
> what velocity is necessary to drive a small rock fragment one meter deep in sand. More
> velocity, I would assume, than would be necessary to drive a bullet a meter deep in sand, since
> a bullet is shaped to penetrate and a meteorite isn't.
> Are there any ballistics experts among us who could tell us what size (and speed) of bullet
> penetrates a meter in loose sand?

You bring up a good point. It turns out a similar report about meteorites
penetrating to a 1 meter depth came also from El Nakhla:

       "this explosion was followed by vapour and a fall of black stones...
        which penetrated the earth to a depth of a metre"

While I had pointed out that William Hume did not do any fieldwork in Denshal, he did
do excellent job of documentation of the meteorites found in El Nakhla. It turns
out no meteorite in El Nakhla penetrated any deeper than 30 cm into the ground.
So, why the discrepancy? Do we just discount the account entirely, and attribute
this as a product of a lively imagination? Or do we just allow for a little leeway
in some of the accounts, as it is obvious they did witness the meteorite fall.
I'd say the latter.

Ron Baalke
Received on Fri 25 Jan 2002 08:52:52 PM PST