Map of observed Gaia-ESO targets on the sky. Observations shown are those included in internal data release 6 (iDR6), covering the entire observing period of the Survey, from 31/12/2011-26/01/2018. Key: MW = Milky Way, CL = Cluster, SD = Standard.

Gaia-ESO is a public spectroscopic survey, targeting ≥ 105 stars, systematically covering all major components of the MilkyWay, from halo to star forming regions, providing the first homogeneous overview of the distributions of kinematics and elemental abundances. This alone will revolutionise knowledge of Galactic and stellar evolution: when combined with Gaia astrometry the survey will quantify the formation history and evolution of young, mature and ancient Galactic populations. With well-defined samples, we will survey the bulge, thick and thin discs and halo components, and open star clusters of all ages and masses. The Fibre Large Array Multi Element Spectrograph (FLAMES) spectra will: quantify individual elemental abundances in each star; yield precise radial velocities for a 4-D kinematic phase-space; map kinematic gradients and abundance - phase-space structure throughout the Galaxy; follow the formation, evolution and dissolution of open clusters as they populate the disc, and provide a legacy dataset that adds enormous value to the Gaia mission and ongoing ESO imaging surveys.

For a top-level description of the project see the overiew article (PDF, large file - 1.98MB).

The internal Gaia-ESO Survey Science Archive, which currently hosts releases up to iDR5, can be found at Meanwhile, iDR6 data products are available to GES co-I's on the GES wiki . Public data releases are available through the ESO Science Portal.  

Gaia-ESO Survey is an ESO project (project 188.B-3002).

The project has received funding from Leverhulme Trust (project RPG-2012-541), European Research Council (project ERC-2012-AdG 320360-Gaia-ESO-MW) and Istituto Nazionale di Astrofisica (INAF) (2012 (CRA:; 2013 (CRA: