This volume consists of papers developed from a joint ACE/ISSI symposium on the "Composition of Matter" honoring the occasion of Johannes Geiss's 80th birthday.

The reader will find new insights into the composition of solar-system and galactic matter and fractionation processes affecting samples of this matter. These findings are based on measurements by recent space instruments, ground-based studies, and theoretical advances. The five symposium sessions reflect the areas of research presented in this book: linking primordial to solar composition, planetary samples, solar sources and fractionation processes, interstellar gas, and cosmic rays.

The structure of the volume at hand largely follows the structure of the symposium. It includes almost all of the overview and invited papers and many of the contributed ones.

Résumé
we thank Johannes for providing us with the occasion to gather in his name and for shaping and supporting the careers of so many of us. May 2007 R. von Steiger, G. Gloeckler, G.M. Mason Space Sci Rev (2007) 130: 34 DOI 10.1007/s11214-007-9240-0 Acknowledgement Published online: 21 July 2007 © Springer Science+Business Media B.V. 2007 Early in 2006, Edward C. Stone, Principal Investigator of NASA's Advanced Composition Explorer (ACE); Len A. Fisk, Chair of the Space Studies Board of the US National Research Council; and the Directorate of the International Space Science Institute (ISSI), Roger M. Bonnet, Andre Balogh and Rudolf von Steiger, agreed to hold a joint ACE/ISSI Symposium on the Composition of Matter, at the occasion of my 80th birthday. I feel deeply honoured by this exceptional distinction and was thrilled to participate, because for more than 50 years my research has been centred around measurements of the composition of matter of various origins, reachingin geocentric coordinatesfrom deep-sea sediments to the limits of solar in uence, where comets come from and where the solar wind meets the interstellar medium. The symposium at Grindelwald, beautifully located at the foot of the Bernese Alps, was organised by Ruedi von Steiger, Silvia Wenger and Barbara Gerber, who created the special atmosphere for which ISSI meetings have become known.

Contenu
Foreword.- Acknowledgement.- Linking Primordial to Solar and Galactic Composition.- Origin and Evolution of the Light Nuclides.- Abundances of Light Elements.- The Milky Way 3-Helium Abundance.- Dark Matter Searches.- Comets and Chemical Composition.- Elemental Abundances of the Bulk Solar Wind: Analyses from Genesis and ACE.- Presolar Grains in Meteorites and Their Compositions.- Planetary Atmospheres.- The Solar Chemical Composition.- Spectroscopic Measurement of Coronal Compositions.- Solar Gamma-Ray Spectroscopy.- The Composition of the Solar Wind in Polar Coronal Holes.- Acceleration and Composition of Solar Wind Suprathermal Tails.- Solar and Solar-Wind Composition Results from the Genesis Mission.- Isotopic Composition of the Solar Wind Inferred from In-Situ Spacecraft Measurements.- Solar Elemental Composition Based on Studies of Solar Energetic Particles.- Solar Isotopic Composition as Determined Using Solar Energetic Particles.- On the Differences in Composition between Solar Energetic Particles and Solar Wind.- What Determines the Composition of SEPs in Gradual Events?.- 3He-Rich Solar Energetic Particle Events.- Evidence for a Two-Stage Acceleration Process in Large Solar Energetic Particle Events.- Particle Acceleration at Interplanetary Shocks.- Ionic Charge States of Solar Energetic Particles: A Clue to the Source.- Pickup Ions and Cosmic Rays from Dust in the Heliosphere.- Composition of Light Solar Wind Noble Gases in the Bulk Metallic Glass flown on the Genesis Mission.- Fe/O Ratios in Interplanetary Shock Accelerated Particles.- The Genesis Solar Wind Concentrator Target: Mass Fractionation Characterised by Neon Isotopes.- Nickel Isotopic Composition and Nickel/Iron Ratio in the Solar Wind: Results from SOHO/CELIAS/MTOF.- Long-Term Fluences ofSolar Energetic Particles from H to Fe.- Determination of Sulfur Abundance in the Solar Wind.- An Update on Ultra-Heavy Elements in Solar Energetic Particles above 10 MeV/Nucleon.- The Local Interstellar Medium: Peculiar or Not?.- The Local Bubble and Interstellar Material Near the Sun.- D/H and Nearby Interstellar Cloud Structures.- Filtration of Interstellar Atoms through the Heliospheric Interface.- Composition of Anomalous Cosmic Rays.- Interstellar Dust in the Solar System.- The Chemical Composition of Interstellar Matter at the Solar Location.- An Overview of the Origin of Galactic Cosmic Rays as Inferred from Observations of Heavy Ion Composition and Spectra.- Galactic Wind: Mass Fractionation and Cosmic Ray Acceleration.- OB Associations, WolfRayet Stars, and the Origin of Galactic Cosmic Rays.- GEMS at the Galactic Cosmic-Ray Source.- The Ultra Heavy Elements in the Cosmic Radiation.- The Composition of Cosmic Rays and the Mixing of the Interstellar Medium.- Johannes Geiss Contributions to the Early Universe Abundances.- Johannes Geiss: The Humble Beginnings of an Octogenarian.- Johannes Geiss' Investigations of Solar, Heliospheric and Interstellar Matter.- Johannes Geiss: Explorer of the Elements.