The Local Interstellar Medium

TL;DR

The paper reviews the structure and influence of the Local Interstellar Medium (LISM) on stellar, planetary, and Earth systems, emphasizing its role in cosmic ray modulation, dust deposition, and potential impacts on climate and biology.

Contribution

It provides a comprehensive overview of the physical conditions, 3D morphology, and effects of the LISM on nearby planetary environments and cosmic phenomena.

Findings

LISM's structure influences cosmic ray modulation and planetary atmospheres.

High-resolution spectroscopy reveals detailed 3D morphology of the LISM.

LISM impacts Earth's climate and biological processes through cosmic ray interactions.

Abstract

The Local Interstellar Medium (LISM) is a unique environment that presents an opportunity to study general interstellar phenomena in great detail and in three dimensions. In particular, high resolution optical and ultraviolet spectroscopy have proven to be powerful tools for addressing fundamental questions concerning the physical conditions and three-dimensional (3D) morphology of this local material. After reviewing our current understanding of the structure of gas in the solar neighborhood, I will discuss the influence that the LISM can have on stellar and planetary systems, including LISM dust deposition onto planetary atmospheres and the modulation of galactic cosmic rays through the astrosphere - the balancing interface between the outward pressure of the magnetized stellar wind and the inward pressure of the surrounding interstellar medium. On Earth, galactic cosmic rays may play a role as contributors to ozone layer chemistry, planetary electrical discharge frequency, biological mutation rates, and climate. Since the LISM shares the same volume as practically all known extrasolar planets, the prototypical debris disks systems, and nearby low-mass star-formation sites, it will be important to understand the structures of the LISM and how they may influence planetary atmospheres.