Interstellar Dust in the Solar System

Abstract

A fraction of the dust in the interstellar medium (ISM) enters the heliosphere and is measured in situ from spacecraft. This review surveys the in situ measurements and discusses a hence derived model of dust in the local interstellar cloud (LIC). The LIC dust model bears similarities to pristine cometary dust and is characteristic of the warm ISM clouds that fill a part of the ISM in the vicinity of the Sun. Recent and future dust in situ measurements provide a basis for closely studying physical processes in the ISM surrounding the Solar System. The LIC dust is the only dust component measurable in the Solar System that was not previously incorporated in larger Solar System objects. Issues for future LIC dust studies are measuring dust fluxes at the outer heliosphere, measuring the mass distribution with meteor observations and observations from spacecraft, and measuring the LIC dust composition in situ in space.