Why Study Interstellar Matter Very Close to the Sun?

Abstract

Interstellar matter (ISM) sets the boundary conditions of the heliosphere and dominates the interplanetary medium. The heliosphere configuration has varied over recent history, as the Sun emerged from the Local Bubble and entered a turbulent outflow of cloudlets originating from the Scorpius-Centaurus Association direction. Several indicators suggest that the local interstellar magnetic field is weak and parallel to the galactic plane. Observations of the interaction products of the ISM with the heliosphere, such as pickup ions and anomalous cosmic rays, when combined with data on the ISM towards nearby stars, provide unique constraints on the composition and physical properties of nearby gas. These data suggest abundances in nearby ISM are subsolar, and that gas and dust are not well mixed at the solar location.

10 pages, 4 figures; Proceedings Houston 2002 COSPAR Outer Heliosphere meeting

References in corpus (18)

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• Low cloud properties influenced by cosmic rays
• Measured Mass Loss Rates of Solar-like Stars as a Function of Age and Activity
• Dust in the Local Interstellar Wind
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• Photospheric Abundances: Problems, Updates, Implications
• Observational Estimates for the Mass-Loss Rates of Alpha Centauri and Proxima Centauri Using HST Lyman-alpha Spectra
• The Ionization of Nearby Interstellar Gas
• Consequences of a Change in the Galactic Environment of the Sun
• Oxygen Gas Phase Abundance Revisited
• Filtration of interstellar hydrogen in the two-shock heliospheric interface: Inferences on the local interstellar electron density
• The Velocity Distribution of the Nearest Interstellar Gas
• The Chemical Composition and Gas-to-Dust Mass Ratio of Nearby Interstellar Matter
• Local clouds: ionization, temperatures, electron densities and interfaces, from GHRS and IMAPS spectra of epsilon Canis Majoris
• Collisional Consequences of Big Interstellar Grains
• Local Interstellar Matter: The Apex Cloud
• Galactic Environment of the Sun and Stars: Interstellar and Interplanetary Material

Cited by in corpus (2)

• Pressure and Ionization Balances in the Circum-Heliospheric Interstellar Medium and the Local Bubble
• Stationary field-aligned MHD flows at astropauses and in astrotails. Principles of a counterflow configuration between a stellar wind and its interstellar medium wind