The GALAH Survey: Observational Overview and Gaia DR1 companion
  The Galactic Archaeology with HERMES (GALAH) Survey is a massive
observational project to trace the Milky Way's history of star formation,
chemical enrichment, stellar migration and minor mergers. Using high-resolution
(R$\simeq$28,000) spectra taken with the High Efficiency and Resolution
Multi-Element Spectrograph (HERMES) instrument at the Anglo-Australian
Telescope (AAT), GALAH will determine stellar parameters and abundances of up
to 29 elements for up to one million stars. Selecting targets from a
colour-unbiased catalogue built from 2MASS, APASS and UCAC4 data, we expect to
observe dwarfs at 0.3 to 3 kpc and giants at 1 to 10 kpc. This enables a
thorough local chemical inventory of the Galactic thin and thick disks, and
also captures smaller samples of the bulge and halo. In this paper we present
the plan, process and progress as of early 2016 for GALAH survey observations.
In our first two years of survey observing we have accumulated the largest
high-quality spectroscopic data set at this resolution, over 200,000 stars. We
also present the first public GALAH data catalogue: stellar parameters (Teff,
log(g), [Fe/H], [alpha/Fe]), radial velocity, distance modulus and reddening
for 10680 observations of 9860 Tycho-2 stars that may be included in the first
Gaia data release.
