[meteorite-list] Any Meteorites of Earth Origin?

From: meteorites_at_space.com <meteorites_at_meteoritecentral.com>
Date: Thu Apr 22 09:47:10 2004
Message-ID: <20011112183728.18671.cpmta_at_c000.snv.cp.net>

On Mon, 12 November 2001, Jeff Grossman wrote:

>
> At 10:46 AM 11/12/2001, meteorites_at_space.com wrote:
> >On Sun, 11 November 2001, Jeff Grossman wrote:
> >
> > >
> > > At 04:34 PM 11/11/2001, meteorites_at_space.com wrote:
> > > >On Sun, 11 November 2001, Jeff Grossman wrote:
> > > >
> > > > >
> > > > > Alan Rubin and I wrote a definition of "meteorite" for Meteorite! a
> > while
> > > > > back that allowed for terrestrial meteorites. Our current thinking is
> > > > that
> > > > > the object would have to have left Earth by natural processes
> > > > > (impact-launching seems the only option, although this is highly
> > > > > improbable), either by achieving escape velocity, or by insertion into
> > > > > Earth orbit via some secondary change to its trajectory (we want to
> > > > > eliminate material on ballistic paths that take it immediately back to
> > > > > Earth, e.g., tektites). If such material later reaccretes to Earth or
> > > > > accretes to another body (like the Moon or an asteroid), we would
> > define
> > > > > this as a terrestrial meteorite.
> > > > >
> > > > > Of course, we already have terrestrial meteorites in our
> > collections if
> > > > the
> > > > > well-accepted theory of lunar formation is correct. But that's just
> > > > > semantics. There is no evidence for more recent events on Earth
> > producing
> > > > > terrestrial meteorites.
> > > > >
> > > > > jeff
> > > >
> > > >
> > > >Tektites, the Australites in particular are "terrestrial meteorites."
> > > >
> > > >Steve Schoner.
> > > >AMS
> > >
> > > What makes you say that?
> > >
> > > Jeff
> > >
> > > Dr. Jeffrey N. Grossman phone: (703) 648-6184
> > > US Geological Survey fax: (703) 648-6383
> > > 954 National Center
> > > Reston, VA 20192, USA
> > >
> >
> >
> >The morphological structure of the Australites (Flanged buttons, flanged
> >dumbells, propeller types) all indicate hypersonic entry into the
> >atmosphere. They were produced in SE Asia, ejected to high altitude,
> >perhpas thousands of miles, traveled in ballistic trajectories to fall in
> >Australia where they are found today.
> >
> >The closest thing to "terrestrial meteorites" if you ask me.
> >...
>
> Close, but no cigar. They did not achieve escape velocity or orbit the
> Earth. They are tektites, not meteorites, by our definition.
>
> jeff
>
>
>

The big question is 'what would "terrestriall meteorites" look like? And would the ejection of such be so violent that the material would be like tektites--- hum something to consider.

Steve Schoner

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Received on Mon 12 Nov 2001 01:37:28 PM PST