Stars in the age of micro-arc-second astrometry

TL;DR

This paper discusses the challenges in modeling stellar interiors and atmospheres, emphasizing how upcoming high-precision observational techniques like micro-arc-second astrometry will enhance our understanding of stars across various types and stages.

Contribution

It highlights current modeling uncertainties and explores how future observational programs will improve the accuracy of stellar property measurements and theoretical models.

Findings

Future astrometric data will refine stellar parameter determinations.

Improved observations will reduce uncertainties in stellar models.

Enhanced models will benefit galactic and cosmological studies.

Abstract

The understanding and modeling of the structure and evolution of stars is based on statistical physics as well as on hydrodynamics. Today, a precise identification and proper description of the physical processes at work in stellar interiors are still lacking (one key point being that of transport processes) while the comparison of real stars to model predictions, which implies conversions from the theoretical space to the observational one, suffers from uncertainties in model atmospheres. That results in uncertainties on the prediction of stellar properties needed for galactic studies or cosmology (as stellar ages and masses). In the next decade, progress is expected from the theoretical, experimental and observational sides. I illustrate some of the problems we are faced with when modeling stars and the possible tracks towards their solutions. I discuss how future observational ground-based or spatial programs (in particular those dedicated to micro-arc-second astrometry, asteroseismology and interferometry) will provide precise determinations of the stellar parameters and contribute to a better knowledge of stellar interiors and atmospheres in a wide range of stellar masses, chemical compositions and evolution stages.