Prospects for Backtracing 1I/`Oumuamua and Future Interstellar Objects

TL;DR

This paper evaluates the feasibility of tracing interstellar objects like 1I/`Oumuamua back to their parent stars, highlighting current limitations and future prospects with improved stellar data and increased ISO discoveries.

Contribution

It provides an analysis of the challenges and potential methods for backtracing interstellar objects to their origins, considering current and upcoming astrometric data.

Findings

Backtracing ISOs is limited by stellar astrometry quality.

Current constraints restrict backtracing to within a few tens of millions of years.

Future data and increased ISO discoveries may improve tracing prospects.

Abstract

1I/`Oumuamua is the first of likely many small bodies of extrasolar origin to be found in the solar system. These interstellar objects (ISOs) are hypothesized to have formed in extrasolar planetary systems prior to being ejected into interstellar space and subsequently arriving at the solar system. This paper discusses necessary considerations for tracing ISOs back to their parent stars via trajectory analysis, and places approximate limits on doing so. Results indicate the capability to backtrace ISOs beyond the immediate solar neighborhood is presently constrained by the quality of stellar astrometry, a factor poised for significant improvement with upcoming Gaia data releases. Nonetheless, prospects for linking 1I or any other ISO to their respective parent star appear unfavorable on an individual basis due to gravitational scattering from random stellar encounters which limit traceability to the past few tens of millions of years. These results, however, do not preclude the possibility of occasional success, particularly after considering the potential for observational bias favoring the discovery of younger ISOs, together with the anticipated rise in the ISO discovery rate under forthcoming surveys.