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Discovery of non-random spatial distribution of
impacts in the Stardust cometary collector.
Westphal A. J., Bastien R. K., Borg J., Bridges J.,
Brownlee D. E., Burchell M. J., Cheng A. F., Clark B. C.,
Djouadi Z., Floss C., Franchi I., Gainsforth Z., Graham G.,
Green S. F., Heck P.R., Horanyi M., Hoppe P., Hörz F.
P., Huth J., Kearsley A., Leroux H., Marhas K.,
Nakamura-Messenger K., Sandford S. A., See T. H., Stadermann
F. J., Teslich N. E., Tsitrin S., Warren J. L.,
Wozniakiewicz P. J., and Zolensky M. E. (2008)
Meteorit. Planet. Sci., in press.
ABSTRACT
We report the discovery that impacts in the Stardust
cometary collector are not distributed randomly in the
collecting media, but appear to be clustered on scales
smaller than ~10 cm. We also report the discovery of at
least two populations of oblique tracks. We evaluated
several hypotheses that could explain the observations. No
hypothesis was consistent with all the observations, but the
preponderance of evidence points toward at least one impact
on the central Whipple shield of the spacecraft as the
origin of both clustering and low-angle oblique tracks.
High-angle oblique tracks unambiguously originate from a
non-cometary impact on the spacecraft bus just forward of
the collector.
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