Abstract:
:The loose material--regolith--on the surfaces of asteroids is thought to represent ballistically emplaced ejecta from impacts but the identification of source craters and the detailed study of the regolith modification have been hampered by the limited spatial resolution and area coverage of the few asteroids imaged by spacecraft. Here we report the results of global mapping of the asteroid 433 Eros from high-resolution images obtained by the NEAR-Shoemaker spacecraft. Based on the images and ejecta-emplacement models, we suggest that most large ejecta blocks on Eros originate from a relatively young 7.6-km-diameter crater. A large fraction of the ejecta from impacts pre-dating that crater has apparently been buried or eroded. The images also show evidence for the action of a variety of sorting environments for regolith particles after they are deposited on the surface.
journal_name
Naturejournal_title
Natureauthors
Thomas PC,Veverka J,Robinson MS,Murchie Sdoi
10.1038/35096513keywords:
subject
Has Abstractpub_date
2001-09-27 00:00:00pages
394-6issue
6854eissn
0028-0836issn
1476-4687pii
35096513journal_volume
413pub_type
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