Lessons learnt from the Solar neighbourhood and the Kepler field

TL;DR

This paper reviews how astrometric and asteroseismic methods applied to stars in the Solar neighbourhood and Kepler field help reconstruct the Milky Way's formation history, emphasizing their complementarity and future prospects.

Contribution

It synthesizes recent studies using astrometric and asteroseismic data to improve Galactic archaeology and discusses future synergies with Gaia and space missions.

Findings

Astrometric and asteroseismic methods complement each other in age-dating stars.

These methods provide key constraints for models of the Milky Way's evolution.

Survey selection should be simplified to basic observables for better results.

Abstract

Setting the timeline of the events which shaped the Milky Way disc through its 13 billion year old history is one of the major challenges in the theory of galaxy formation. Achieving this goal is possible using late-type stars, which in virtue of their long lifetimes can be regarded as fossil remnants from various epochs of the formation of the Galaxy. There are two main paths to reliably age-date late-type stars: astrometric distances for stars in the turn-off and subgiant region, or oscillation frequencies along the red giant branch. So far, these methods have been applied to large samples of stars in the solar neighbourhood, and in the Kepler field. I review these studies, emphasize how they complement each other, and highlight some of the constraints they provide for Galactic modelling. I conclude with the prospects and synergies that astrometric (Gaia) and asteroseismic space-borne missions reserve to the field of Galactic Archaeology, and advocate that survey selection functions should be kept as simple as possible, relying on basic observables such as colours and magnitudes only.