* Astronomy

Title: Primordial gases in the Jodzie howardite and the origin of gas-rich meteorites
Authors: Mazor, Emanuel; Anders, Edward

The dark portion of Jodzie contains primordial gases at nearly the same levels as Kapoeta, another brecciated howardite. All five gases, He--Xe, are enriched twofold in a magnetic concentrate relative to an unfractionated sample. A similar enrichment is shown by Ni. The uniform enrichment of the gases shows that the solar and planetary components are covariant, and were presumably introduced together. Much smaller amounts of gas are found in the light portion. The dark portions of Jodzie and several gas-rich meteorites are enriched in Kr, Xe, C, Ni, Br and Bi in nearly the exact proportions in which these elements occur in carbonaceous chondrites. This supports the suggestion of and that the noble gases were introduced via a "carrier" of carbonaceous chondrite composition, admixed to a level of 1-15 %. Presumably this "carrier" consisted of interplanetary dust bombarded by the solar wind, which was accreted by the meteorite parent bodies and then incorporated in a breccia during impact. Apparently material of carbonaceous chondrite composition comprises a major part of the dust in the asteroid belt. The saturation level of He 4 in interplanetary dust is estimated as 1 x 10 18 -3 x 10 19 atoms/g, in good agreement with the He 4 content in the "carrier" inferred from the observed gas and trace element content of gas-rich meteorites.

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