[meteorite-list] Peruvian bolide rehash post #4

From: Matson, Robert <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Fri, 2 Mar 2007 15:22:53 -0800
Message-ID: <A8044CCD89B24B458AE36254DCA2BD070321B609_at_0005-its-exmp01.us.saic.com>

My reply to Randall's post (#3):

- - - - -
Sent: 3/1/2007 7:37pm PST

Randall,

> Enclosed is the workshop brief on small impact cratering. You can
> see the velocities associated even with small craters.
> http://www.lpi.usra.edu/meetings/impact2003/pdf/8004.pdf

Well of course! But you don't seem to understand that cratering events
don't go unnoticed. If a Campo del Cielo-type fall occurred today over
land, the world would know about it, not just Peru. Even with Campo's
huge size and multiple impact craters, the impact velocity was still
less than 5 km/sec. So you see that claiming an impact velocity of
15 km/sec for the Peru event is completely out of the question.

Sikhote-Alin is perhaps a closer analog to the event you are claiming
occurred over Peru, but Sikhote-Alin was far more than 1 kiloton.

> Could you define your area of expertise. I'm not questioning it,
> just curious.

Short answer is that I'm a space scientist. I've modeled hypersonic
reentries for many bolides (including Park Forest and the western
Washington bolide) as well as Columbia Space Shuttle debris, and have
solved a number of bolide triangulation problems over the last 5 years.
I'm also an orbital dynamicist, working on a wide variety of problems
in astrodynamics - impact rate predictions, Yarkovsky and YORP effects,
minor planet evolution. In the course of these studies I've discovered
60 sungrazing comets and over a thousand minor planets, and have
submitted astrometric data for over 180 near-earth asteroids.

> I sent you the seismic waveforms.
> I'm waiting... 29, 28, 27, 26 :)

Just for the record (for those folks reading along), Randall sent me
five ASCII files with headers, each followed by long lists of integers.
These were the so called "waveforms". Randall, I suppose I should be
flattered that you believe that by inspection I'll be able to interpret
a few thousand numbers and give you an instant answer, but RainMan I'm
not. ;-) With a few hours' work I could convert this data into a
usable product, but having a few beers sounds like a more enjoyable
use of my time right this instant...

--Rob
Received on Fri 02 Mar 2007 06:22:53 PM PST