[meteorite-list] Re: Deciphering Denshal Dog Data

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu Apr 22 09:52:13 2004
Message-ID: <200208131722.KAA17801_at_zagami.jpl.nasa.gov>

>Even though my skeptical nature leads me to scrutinize the impact dog
>event, I remain open-minded to any new evidence supporting either side.

No one asks for anything more.

>While looking through the literature for any helpful data, I found a
>"non-peer-reviewed" paper, published by Eugster et al. in LPSC 33
>(2002), in which they describe research on "The Pre-Atmospheric Size Of
>Martian Meteorites".

Thanks for pointing out the paper.
Did the paper include the two Nakhlites found in the Antarctic? They have
been paired and have a combined weight of 15 kg, which is the second largest
meteorite fall for a Mars meteorite.

>While this is admittedly only a tiny stab, I think there might be other
>data out there, which taken together, could establish a preponderance of
>evidence and tip the scale one way or the other.

Another consideration for the Nakhla strewnfield is the angle of trajectory
through the atmosphere. Nahkla had a very inclined path, just 30 degrees from the
horizontal. If the fall had come straight down vertically, then the
strewnfield would be confined to a relatively small area. But if the meteorites
followed along an extremely inclined path, such as the case with Nakhla,
then the strewnfield will be very elongated and the meteorites fragments will be
much more spread out. John Ball also reported the Nakhla meteorite exploded
"at a considerable altitude in the air". He didn't say what that altitude was,
but anything exploding at an high altitude will have its fragments more dispersed
on the ground than something exploding at a lower altitude. Combine that with
the meteorite's high inclination, you then have a case for a large strewnfield
for the Nakhla meteorite.

Ron Baalke
Received on Tue 13 Aug 2002 01:22:05 PM PDT