Orbital Dynamics and the Evolution of Planetary Habitability in the AU Mic System

TL;DR

This study investigates the orbital dynamics and habitability evolution of planets in the young, nearby AU Mic system, focusing on habitable zone changes, atmospheric processes, and long-term orbital stability during early stellar phases.

Contribution

It provides the first detailed analysis of the habitable zone evolution and orbital stability of planets in the AU Mic system during its early stages, including pre-main sequence effects.

Findings

Habitable zone shifts significantly during the system's early evolution.

Terrestrial planets can maintain long-term stability within the habitable zone.

Rapid eccentricity evolution affects planetary climate and habitability prospects.

Abstract

The diversity of planetary systems that have been discovered are revealing the plethora of possible architectures, providing insights into planet formation and evolution. They also increase our understanding of system parameters that may affect planetary habitability, and how such conditions are influenced by initial conditions. The AU~Mic system is unique among known planetary systems in that it is a nearby, young, multi-planet transiting system. Such a young and well characterized system provides an opportunity to study orbital dynamical and habitability studies for planets in the very early stages of their evolution. Here, we calculate the evolution of the Habitable Zone of the system through time, including the pre-main sequence phase that the system currently resides in. We discuss the planetary atmospheric processes occurring for an Earth-mass planet during this transitionary period, and provide calculations of the climate state convergence age for both volatile rich and poor initial conditions. We present results of an orbital dynamical analysis of the AU~Mic system that demonstrate the rapid eccentricity evolution of the known planets, and show that terrestrial planets within the Habitable Zone of the system can retain long-term stability. Finally, we discuss follow-up observation prospects, detectability of possible Habitable Zone planets, and how the AU Mic system may be used as a template for studies of planetary habitability evolution.