A dynamical test for terrestrial planets in the habitable zone of HD 204313

TL;DR

This study analyzes the dynamical stability of the HD 204313 system to identify potential habitable zones for Earth-like planets, finding limited stability due to resonances, and establishing a framework for future searches.

Contribution

It introduces a dynamical analysis method for assessing habitable zones in multi-planet systems, focusing on HD 204313, and sets up a larger project for future stability studies.

Findings

Two semi-stable regions identified in HD 204313

Resonances likely cause semi-stability

No long-term stable habitable zone found

Abstract

With improvements in exoplanet detection techniques, the number of multiple planet systems discovered is increasing, while the detection of potentially habitable Earth-mass planets remains complicated and thus requires new search strategies. Dynamical studies of known multiple planet systems are therefore a vital tool in the search for stable and habitable planet candidates. Here, we present a dynamical study of the three-planet system HD 204313 to determine whether it could harbour an Earth-like planet within its habitable zone for a sufficient time to develop life. We found two semi-stable regions in the system, but neither prove stable for long enough for a terrestrial planet to develop life. Our investigations suggest that overlapping weak and high order resonances may be responsible for these semi-stable regions. This study established a framework for a larger project that will study the dynamical stability of the habitable zone of multiple planet systems, providing a list of interesting targets for future habitable low-mass planet searches.