[meteorite-list] H, L, and LL parent bodies

From: Jamie Stephens <j.stephens_at_meteoritecentral.com>
Date: Thu Apr 22 10:27:53 2004
Message-ID: <3FC3706C.3080700_at_morphism.com>

List Members,

Speaking of parent bodies, I've seen references to "the"
H parent body. Likewise the L and LL parent bodies.

David Weir writes

   [T]he H parent body suffered two distinct collisional
   events [...] The H chondrites are a good spectrographic
   match with the S(IV)-type asteroids 6 Hebe, 3 Juno, and
   7 Iris.

For H, L, and LL chondrites, what's the evidence that each
group has a single parent body? Or is "the H parent body"
shorthand for "the collection of bodies that are the
sources for H chondrites"?

For an HED, a Vestoid could be the source body, which
presumably has 4 Vesta as its parent. In such a case,
4 Vesta would be the grandparent body -- the terminal
source. It's odd reflectance spectra is (I think)
strong evidence for the singular (grand)parent body
conclusion in this case. Call 4 Vesta *the* HED
"primordial" parent body -- or something like that.

In contrast, why rule out multiple primoridial H parent
bodies, each with similar compositions due to, say, origin
in the same, large nebular resevoir? Are H/L transitionals
evidence agaist a singular H parent body?

Seems like the phrase "H parent bodies" better reflects
current knowledge than the phrase "the H parent body". No?

--Jamie Stephens
Received on Tue 25 Nov 2003 10:08:28 AM PST