Exobodies in Our Back Yard: Science from Missions to Nearby Interstellar Objects

TL;DR

This paper discusses the potential for spacecraft missions to nearby interstellar objects, which are accessible exobodies, to gain insights into galactic evolution, planetary formation, and astrobiology, within the 2023-2032 decade.

Contribution

It highlights the feasibility and scientific value of in situ exploration of interstellar objects using current spacecraft technology.

Findings

Spacecraft can determine ISO structure and composition during flybys.

Technology useful for missions to TNOs and comets.

ISO exploration can improve understanding of galactic and planetary processes.

Abstract

The recent discovery of the first confirmed Interstellar Objects (ISOs) passing through the Solar System on clearly hyperbolic objects opens the potential for near term ISO missions, either to the two known objects, or to similar objects found in the future. Such ISOs are the only exobodies we have a chance of accessing directly in the near future. This White Paper focuses on the science possible from in situ spacecraft exploration of nearby ISOs. Such spacecraft missions are technically possible now and are suitable potential missions in the period covered by the 2023-2032 Decadal Survey. Spacecraft missions can determine the structure and the chemical and isotopic composition of ISO in a close flyby coupled with a small sub-probe impactor and either a mass spectrometer or a high resolution UV spectrometer; this technology will also be useful for fast missions to TransNeptune Objects (TNOs) and long period comets. ISO exploration holds the potential of providing considerable improvements in our knowledge of galactic evolution, of planetary formation, and of the cycling of astrobiologically important materials through the galaxy.