Interaction between Winds from Weak-lined T Tauri Stars with Exoplanetary Magnetospheres

TL;DR

This study examines how stellar winds from weak-lined T Tauri stars impact the magnetospheres of Earth-like exoplanets, revealing significant compression due to strong stellar winds and magnetic pressures.

Contribution

It introduces a comparative analysis of stellar wind models and their effects on exoplanetary magnetospheres around WTTSs, highlighting the influence of stellar age and magnetic activity.

Findings

Planetary magnetospheres are significantly compressed by WTTS stellar winds.

Magnetospheric sizes increase as stellar magnetic activity decays with age.

Both magnetized and nonmagnetized wind models show similar pressure effects.

Abstract

T Tauri stars, in more advanced stages of evolution, during the final accretion phase of stellar formation, exhibit intense stellar winds and surface magnetic fields with intensities around a kilogauss. With the growing interest in the search for rocky exoplanets with Earth-like dimensions, it is essential to deepen our understanding of the interaction between stellar winds and planetary magnetospheres. We investigated the interaction between stellar winds from 46 weak-lined T Tauri stars (WTTSs) and the magnetospheric protection of Earth-like planets located within their habitable zones. We employ two distinct stellar wind models, nonmagnetized and magnetized with both constant and resonant Alfven wave damping, to evaluate the pressure balance between the stellar wind and the planetary magnetic field. Our results show that the strong wind dynamic and magnetic pressures characteristic of WTTSs lead to systematically compressed planetary magnetospheres, significantly smaller than that of the present-day Earth. The analysis further indicates that planetary magnetospheric sizes increase with stellar age, following the decay of stellar magnetic activity, in agreement with previous findings for solar-type stars.