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arXiv · 2310.00860

Surrounded by Giants: Habitable Zone Stability Within the HD 141399 System

Abstract

The search for exoplanets has revealed a diversity of planetary system architectures, the vast majority of which diverge significantly from the template of the solar system. In particular, giant planets beyond the snow line are relatively rare, especially for low-mass stars, placing the solar system within a small category of systems with multiple giant planets at large separations. An exoplanetary system of note is that of HD 141399, consisting of a K dwarf host star that harbors four giant planets with separations extending to $\sim$4.5 AU. The architecture of the system creates a complex pattern of mean motion resonances and gravitationally perturbed regions that may exclude the presence of other planets, including within the Habitable Zone of the system. Here, we present the results of dynamical simulations that explore the interaction of the known planets of the system, their apsidal trajectories, resonance locations, and dynamical evolution. We further investigate the results of injecting Earth-mass planets and provide the regions of dynamical viability within the Habitable Zone where terrestrial planets may maintain long-term stability. We discuss these results in the context of the importance of giant planets for volatile delivery and planetary habitability considerations.

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Stephen R. Kane. 2023-10-02. Surrounded by Giants: Habitable Zone Stability Within the HD 141399 System. https://arxiv.org/abs/2310.00860

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