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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 >25,00 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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