title: Distribution of phyllosilicates on the surface of Ceres.
abstract: The dwarf planet Ceres is known to host phyllosilicate minerals at its surface, but their distribution and origin have not previously been determined. We used the spectrometer onboard the Dawn spacecraft to map their spatial distribution on the basis of diagnostic absorption features in the visible and near-infrared spectral range (0.25 to 5.0 micrometers). We found that magnesium- and ammonium-bearing minerals are ubiquitous across the surface. Variations in the strength of the absorption features are spatially correlated and indicate considerable variability in the relative abundance of the phyllosilicates, although their composition is fairly uniform. These data, along with the distinctive spectral properties of Ceres relative to other asteroids and carbonaceous meteorites, indicate that the phyllosilicates were formed endogenously by a globally widespread and extensive alteration process.
authors.affiliation: Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA. eleonora.ammannito@igpp.ucla.edu.
authors.forename: E
authors.initials: E
authors.lastname: Ammannito
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: M C
authors.initials: MC
authors.lastname: DeSanctis
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Ciarniello
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Frigeri
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: F G
authors.initials: FG
authors.lastname: Carrozzo
authors.affiliation: The Bear Fight Institute, Winthrop, WA 98862, USA.
authors.forename: J-Ph
authors.initials: JP
authors.lastname: Combe
authors.affiliation: Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: B L
authors.initials: BL
authors.lastname: Ehlmann
authors.affiliation: Southwest Research Institute, Boulder, CO 80302, USA.
authors.forename: S
authors.initials: S
authors.lastname: Marchi
authors.affiliation: Department of Earth and Planetary Sciences, University of Tennessee, Knoxville, TN 37996-1410, USA.
authors.forename: H Y
authors.initials: HY
authors.lastname: McSween
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Raponi
authors.affiliation: Institut de Recherche en Astrophysique et Planétologie (UMR 5277), Université de Toulouse, F-31400 Toulouse, France.
authors.forename: M J
authors.initials: MJ
authors.lastname: Toplis
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Tosi
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: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Capaccioni
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: M T
authors.initials: MT
authors.lastname: Capria
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Fonte
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Giardino
authors.affiliation: Institute of Planetary Research, Deutsches Zentrum für Luft- und Raumfahrt, 12489 Berlin, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Jaumann
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Longobardo
authors.affiliation: Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.
authors.forename: S P
authors.initials: SP
authors.lastname: Joy
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: G
authors.initials: G
authors.lastname: Magni
authors.affiliation: The Bear Fight Institute, Winthrop, WA 98862, USA.
authors.forename: T B
authors.initials: TB
authors.lastname: McCord
authors.affiliation: NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA.
authors.forename: L A
authors.initials: LA
authors.lastname: McFadden
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: E
authors.initials: E
authors.lastname: Palomba
authors.affiliation: Department of Earth, Environmental, and Planetary Sciences, Brown University, Providence, RI 02912, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Pieters
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Polanskey
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Rayman
authors.affiliation: Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA.
authors.forename: C A
authors.initials: CA
authors.lastname: Raymond
authors.affiliation: Lunar and Planetary Institute, Houston, TX 77058, USA.
authors.forename: P M
authors.initials: PM
authors.lastname: Schenk
authors.affiliation: Istituto di Astrofisica e Planetologia Spaziali, Istituto Nazionale di Astrofisica, 00133 Roma, Italy.
authors.forename: F
authors.initials: F
authors.lastname: Zambon
authors.affiliation: Earth Planetary and Space Sciences, University of California-Los Angeles, 603 Charles Young Drive, Los Angeles, CA 90095-1567, USA.
authors.forename: C T
authors.initials: CT
authors.lastname: Russell