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Isotopic compositions of cometary matter
returned by the STARDUST mission.
McKeegan K., Aléon J., Alexander C., Bradley
J., Brownlee D., Burnard P., Butterworth A., Chaussidon M.,
Davis A., Floss C., Gilmour J., Guan Y., Hohenberg C., Hoppe
P., Hutcheon I., Ito M., Jacobsen S., Leshin L., Lyon I.,
Marhas K., Marty B., Meibom A., Meshik A., Messenger S.,
Nakamura K., Nittler L., Palma R., Pellin M., Pepin R., Tsou
P., Robert F., Schlutter D., Stadermann F. J., Stroud R.,
Westphal A., Young E., Ziegler K., and Zinner E. (2006)
Meteorit. Planet. Sci. 41, Abstract #5300.
ABSTRACT
The STARDUST spacecraft flew through the coma of comet
81P/Wild2 on Jan. 2, 2004, at a distance of ~236 km and a
relative velocity of ~6.1 km/s. Dust particles, which were
released from the comet hours before the encounter, were
captured in silica aerogel and successfully returned to the
Earth on Jan. 15, 2006. Cometary debris was also retained in
small impact craters on Al-foil strips adjacent to the
aerogel collector cells. A prelimary examination team (PET)
of ~150 scientists has been engaged in studying the
mineralogy/petrology, chemistry, optical properties, organic
materials, fluence, and isotopic compositions of a subset of
the returned cometary materials. This report will summarize
what has been learned regarding isotopic compositions of
select elements by the PET during its 6 month
investigation.
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