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Isotopically primitive interplanetary dust
particles of cometary origin: evidence from nitrogen
isotopic compositions
Floss C. and Stadermann F. J. (2004)
Lunar and Planetary Science XXXV, Abstract #1281, LPI
Houston.
ABSTRACT
The presence of large and variable H and N isotopic
anomalies in interplanetary dust particles (IDPs) is
well-established and attests to the primitive nature of the
material present in IDPs. Last year we reported on the C, N
and O isotopic systematics of two unusual IDPs. Both contain
grains with highly anomalous O isotopic compositions,
indicative of a presolar origin, and exhibit N isotopic
anomalies, in the form of 15N enriched bulk
compositions as well as more localized enrichments in
15N (up to +1270 permil). Moreover, a
15N-rich hotspot in one IDP contains the first C
isotopic anomaly reported in IDPs. With the extension of our
isotopic imaging survey to additional IDPs, we confirm the
existence of a subgroup of IDPs with primitive isotopic
characteristics.
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