[meteorite-list] Never underestimate or dismiss Spectroscopy

From: Benjamin P. Sun <bpsun2009_at_meteoritecentral.com>
Date: Wed, 16 May 2012 21:04:11 -0400
Message-ID: <CAE1PX87QWN=G+sp5gNMYJvYd8ycrxVHLiPhSiMcyfrNPp9YTYQ_at_mail.gmail.com>

If a dealer or someone were to claim that their Tatahouine or NWA 2060
came from Vesta, I would not counter or argue with him. Simply because
he has more evidence and proof pointing his way now. You should say
that the(<1%) rare odd non-Vestan ungrouped anomalous "eucrite" may or
may not be from Vesta instead.

At this time, a sample return mission from Mars, Phobos, Europa or
Titan would make more sense than a sample return mission from Vesta.

On 5/16/12, Benjamin P. Sun <bpsun2009 at gmail.com> wrote:
> "Generally speaking, stating to the HED clan of meteorites are mainly
> derived from "Vesta" is acceptable so long as we understand ( Caveat
> #1) that they could also be from any of the Vesta family: any of
> those 6000+ bodies populating the Vesta orbital region. Many of
> those are over 1 km size and most but not all have Vesta matching
> spectra/albedos."
>
>
> I'd consider that the many Vestiods of the Vesta family were and are
> still pieces of their parent body, Vesta. Not counting the odd
> interloper or co-habitant of the group region, of course.
> Just like the many martian and lunar meteoriods(martianiod? lunoid?)
> out there floating in space, blasted off their PB's, were and still
> are considered pieces of Mars and the Moon respectively.
> Speaking for myself, it matters very little whether my HED came from
> Vesta directly or indirectly from a Vestiod. In the end, it's still
> from Vesta.
>
>
> "The second caveat is covered elsewhere in recent list commentary: the
> fact that we do have some non-Vestian eucrites was panned as
> "insignificant". Well, Au contraire-- the existence of a but a
> solitary example is proof that the "basaltic, sub/minor-planetary
> differentiation process" happened on more than a single body. Adding
> credibility to the planetary-science model. Naively stating over
> and over that "all eucrites " come from Vesta" won't make it true.
> Doing so retards the advancement meteorite science."
>
>
> Keep in mind that the word "eucrite" and "eucritic" was a rather broad
> and loosely used term back in the (old) day(s). Scientists now are
> more specific in it's usage, accurate and clear with their
> classifications . So some of those old eucrites and rare "non-Vestian
> eucrites" need to be re-examined and possibly reclassified.
>
>
> From Wikipedia:
>
> "Eucrites are achondritic stony meteorites, many of which originate
> from the surface of the asteroid 4 Vesta and as such are part of the
> HED meteorite group. They are the most common achondrite group with
> well over 100 distinct finds at present.
>
> Eucrites consist of basaltic rock from the crust of 4 Vesta or a
> similar parent body. They are mostly composed of Ca-poor pyroxene,
> pigeonite, and Ca-rich plagioclase (anorthite)."
>
>
> I happen to agree with this definition. Also:
>
>
> "Eucrites get their name from the Greek word eukritos meaning "easily
> distinguished". This refers to the silicate minerals in them, which
> can be easily distinguished because of their relatively large grain
> size.
>
> Eucrite is also a now obsolete term for bytownite-gabbro found on
> Earth. The term was used as a rock type name for some of the Paleogene
> igneous rocks of Scotland."
>
Received on Wed 16 May 2012 09:04:11 PM PDT