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Re: Meteorites from Earth and Venus

Hi,

in his very interesting posting Bernd Pauli mentiones the possibility of
meteorites found on earth coming from Venus.

Sure those specimens should be young, basaltic achondrites. But given our
current understanding of Venus - is there more we could say ? What could be
their composition and how would these meteorites look like ?

Does anyone dare to guess ? 

.................................................
Christian Pinter, Ph.D.   Journalist
Address: Gerichtsgasse 1c/6/10
A-1210  Vienna, Austria (Europe)
Email to: pinter@ping.at
http://members.ping.at/pinter

----------
> Von: Bernd Pauli 
> An: meteorite-list@meteoritecentral.com
> Betreff: Meteorites from Earth and Venus
> Datum: Dienstag, 05. Mai 1998 23:33
> 
> Hello List,
> 
> There is a very interesting abstract in METEORITICS which touches both
> on the current topic of meteorites found in lunar samples, the Venus
> topic we had some days ago, and Ron's contribution:
> 
> > It is also interesting to note that no Earth meteorites have been
> > found (stony rocks), though there should be some that exist.  I'd
> > assume they haven't been found yet because an Earth meteorite would
> > have to be a very recent fall, as once it loses its fusion crust due
> > to exposure to weather and the elements, it would be indistinguishable
> > from a regular Earth rock.
> 
> 
> 
> 
> MELOSH H.J. et al. (1993) Swapping rocks: Ejection and exchange of
> surface material among the terrestrial planets (Meteoritics 28-3, 1993,
> A398, Excerpts):
> 
> The discovery of meteorites originating from both the Moon and Mars has
> led to the realization that major impacts can eject material from
> planet-sized objects. Although there is not yet any direct proof, there
> appears to be no reason why such impacts cannot  eject material from the
> surfaces of Earth and Venus as well.
> 
> Mercury ejecta is nearly all reaccreted by Mercury or erodes in space
> ... ( a few percent impact Venus).
> 
> Venus ejecta is mostly reaccreted by Venus, but a significant fraction
> (about 30%) falls on the Earth ...
> 
> Earth ejecta is also mainly reaccreted by the Earth but about 30% strike
> Venus ...
> 
> The larger planets, Venus and Earth,thus readily exchange ejecta. Mars
> ejecta largely falls on Venus and Earth, but Mars only receives a small
> fraction of their ejecta. A substantial fraction of ejecta from all the
> terrestrial planets (except Mercury) is thrown out of the solar system
> by Jupiter ...
> 
> ... we should expect someday to find meteorites from Earth itself and
> from Venus.
> 
> Best wishes, Bernd
>