title: Cratering on Ceres: Implications for its crust and evolution.
abstract: Thermochemical models have predicted that Ceres, is to some extent, differentiated and should have an icy crust with few or no impact craters. We present observations by the Dawn spacecraft that reveal a heavily cratered surface, a heterogeneous crater distribution, and an apparent absence of large craters. The morphology of some impact craters is consistent with ice in the subsurface, which might have favored relaxation, yet large unrelaxed craters are also present. Numerous craters exhibit polygonal shapes, terraces, flowlike features, slumping, smooth deposits, and bright spots. Crater morphology and simple-to-complex crater transition diameters indicate that the crust of Ceres is neither purely icy nor rocky. By dating a smooth region associated with the Kerwan crater, we determined absolute model ages (AMAs) of 550 million and 720 million years, depending on the applied chronology model.
authors.affiliation: Institut für Planetologie, Westfälische Wilhelms-Universität, Münster, Germany. hiesinger@uni-muenster.de.
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authors.lastname: Hiesinger
authors.affiliation: Southwest Research Institute, Boulder, CO 80302, USA.
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authors.lastname: Marchi
authors.affiliation: Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany.
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authors.affiliation: Lunar and Planetary Institute, Houston, TX 77058, USA.
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authors.affiliation: Institut für Planetologie, Westfälische Wilhelms-Universität, Münster, Germany.
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authors.lastname: Pasckert
authors.affiliation: Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany.
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authors.lastname: Neesemann
authors.affiliation: Planetary Science Institute, Tucson, AZ 85719, USA.
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authors.affiliation: Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany.
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authors.affiliation: Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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authors.affiliation: Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
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authors.affiliation: U.S. Geological Survey, Astrogeology Science Center, Flagstaff, AZ 86001, USA.
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authors.lastname: Bland
authors.affiliation: Max-Planck Institute for Solar System Research, Göttingen, Germany.
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authors.affiliation: Max-Planck Institute for Solar System Research, Göttingen, Germany.
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authors.lastname: Platz
authors.affiliation: Arizona State University, Tempe, AZ 85281, USA.
authors.forename: D A
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authors.lastname: Williams
authors.affiliation: German Aerospace Center (DLR), Berlin, Germany. Institute of Geological Sciences, Freie Universität Berlin, Berlin, Germany.
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authors.lastname: Jaumann
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Castillo-Rogez
authors.affiliation: NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
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authors.lastname: Ruesch
authors.affiliation: Georgia Institute of Technology, Atlanta, GA 30332, USA.
authors.forename: B
authors.initials: B
authors.lastname: Schmidt
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
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authors.initials: RS
authors.lastname: Park
authors.affiliation: German Aerospace Center (DLR), Berlin, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Preusker
authors.affiliation: John Hopkins Applied Physics Laboratory, Laurel, MD 20723, USA.
authors.forename: D L
authors.initials: DL
authors.lastname: Buczkowski
authors.affiliation: Department of Earth and Space Sciences, University of California, Los Angeles, CA 90095, USA.
authors.forename: C T
authors.initials: CT
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authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: C A
authors.initials: CA
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