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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 (8, Suppl.), A119.
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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