The Early Merger that Made the Galaxy's Stellar Halo

Abstract

The last two years have seen widespread acceptance of the idea that the Milky Way halo was largely created in an early (8-10 Gyr ago) and massive ($>10^{10}{M}_{\odot }$) merger. The roots of this idea pre-date the Gaia mission, but the exquisite proper motions available from Gaia have made the hypothesis irresistible. We trace the history of this idea, reviewing the series of papers that led to our current understanding.

arXiv comment8 page text of invited review at IAU Symposium 353 `Galactic dynamics in the era of large surveys' (Eds M. Valluri, J. Sellwood)

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Cited by in corpus (9)

• Reconstructing the Last Major Merger of the Milky Way with the H3 Survey
• Chemo-kinematics of the $Gaia$ RR Lyrae: the halo and the disc
• Evidence for sub-Chandrasekhar Type Ia supernovae from the last major merger
• The dark matter component of the Gaia radially anisotropic substructure
• The impact of the Large Magellanic Cloud on dark matter direct detection signals
• Star Formation Timescales of the Halo Populations from Asteroseismology and Chemical Abundances
• Two Populations of Carbon-Enhanced Metal-Poor Stars in the Disk System of the Milky Way
• Observing EAGLE galaxies with JWST: predictions for Milky Way progenitors and their building blocks
• AuriDESI: Mock Catalogues for the DESI Milky Way Survey