title: Flux and composition of interstellar dust at Saturn from Cassini's Cosmic Dust Analyzer.
abstract: Interstellar dust (ISD) is the condensed phase of the interstellar medium. In situ data from the Cosmic Dust Analyzer on board the Cassini spacecraft reveal that the Saturnian system is passed by ISD grains from our immediate interstellar neighborhood, the local interstellar cloud. We determine the mass distribution of 36 interstellar grains, their elemental composition, and a lower limit for the ISD flux at Saturn. Mass spectra and grain dynamics suggest the presence of magnesium-rich grains of silicate and oxide composition, partly with iron inclusions. Major rock-forming elements (magnesium, silicon, iron, and calcium) are present in cosmic abundances, with only small grain-to-grain variations, but sulfur and carbon are depleted. The ISD grains in the solar neighborhood appear to be homogenized, likely by repeated processing in the interstellar medium.
authors.affiliation: European Space Agency, European Space Astronomy Centre, Madrid, Spain. nicolas.altobelli@sciops.esa.int.
authors.forename: N
authors.initials: N
authors.lastname: Altobelli
authors.affiliation: Institut für Geowissenschaften, University of Heidelberg, Heidelberg, Germany. Institut für Raumfahrtsysteme, University of Stuttgart, Stuttgart, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Postberg
authors.affiliation: Institut für Geowissenschaften, University of Heidelberg, Heidelberg, Germany. Georgia Institute of Technology, School of Chemistry and Biochemistry, Atlanta, GA, USA.
authors.forename: K
authors.initials: K
authors.lastname: Fiege
authors.affiliation: Institut für Geowissenschaften, University of Heidelberg, Heidelberg, Germany. Klaus-Tschira-Labor für Kosmochemie, University of Heidelberg, Heidelberg, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Trieloff
authors.affiliation: Kobe University, Kobe, Hyōgo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kimura
authors.affiliation: International Space Sciences Institute, Bern, Switzerland.
authors.forename: V J
authors.initials: VJ
authors.lastname: Sterken
authors.affiliation: University of Boulder, Boulder, CO, USA.
authors.forename: H-W
authors.initials: HW
authors.lastname: Hsu
authors.affiliation: University of Kent, Kent, UK.
authors.forename: J
authors.initials: J
authors.lastname: Hillier
authors.affiliation: Institut für Raumfahrtsysteme, University of Stuttgart, Stuttgart, Germany.
authors.forename: N
authors.initials: N
authors.lastname: Khawaja
authors.affiliation: Institut für Raumfahrtsysteme, University of Stuttgart, Stuttgart, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Moragas-Klostermeyer
authors.affiliation: Technische Universität Braunschweig, Institut für Geophysik und Extraterrestrische Physik, Braunschweig, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Blum
authors.affiliation: Jet Propulsion Laboratory, Pasadena, CA, USA.
authors.forename: M
authors.initials: M
authors.lastname: Burton
authors.affiliation: Institut für Raumfahrtsysteme, University of Stuttgart, Stuttgart, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Srama
authors.affiliation: University of Boulder, Boulder, CO, USA.
authors.forename: S
authors.initials: S
authors.lastname: Kempf
authors.affiliation: Institut für Geowissenschaften, University of Heidelberg, Heidelberg, Germany. Institut für Raumfahrtsysteme, University of Stuttgart, Stuttgart, Germany. University of Boulder, Boulder, CO, USA.
authors.forename: E
authors.initials: E
authors.lastname: Gruen