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Preliminary examination of the interstellar collector of
Stardust.
Westphal A., Allen C., Bastien R., Borg J., Brenker F.,
Bridges J., Brownlee D., Butterworth A., Floss C., Flynn G., Frank D.,
Gainsforth Z., Grun E., Hoppe P., Kearsley A., Leroux H., Nittler L.,
Sandford S., Simionovici A., Stadermann F. J., Stroud R., Tsou P.,
Tyliczszak T., Warren J., Zolensky M., and >23,000 Stardust@home
dusters (2008)
Lunar & Planet. Sci.39, Abstract #1855.
ABSTRACT
In January 2006, the Stardust spacecraft returned to earth two
unprecedented and independent extraterrestrial samples: the first bona
fide samples of a comet, and the first samples of contemporary
interstellar dust. The Preliminary Examination (PE) of the cometary
collection was a planned part of the mission and took place in the
first months after recovery. Results of the cometary PE were reported
in a special issue of Science. Approximately 85% of the 1039 cm2
collector area of the Stardust Interstellar tray consists of aerogel
tiles, and the remaining area consists of aluminum foils. The
collection timewas 196 days. The recent incorporation of data from
varying heliocentric distances and better understanding of particle
size filtering as a function of approach to Solar Maximum now suggest
that an interstellar particle flux of > 7 x 10-5 m-2
s-1 might have been expected at the relatively modest
heliocentric distance (~ 2.0 - 2.5 AU). With the simplifying assumption
that the flux was constant over the collection periods, this would
imply ~120 particles >300 nm in size to have hit aerogel and ~15 to
have impacted the aluminum foil
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