How did the Milky Way form? Which mergers shaped it? Where were its stars born?

For the past decade, the GALactic Archaeology with HERMES (GALAH) survey has mapped the chemical fingerprints of nearly one million stars, transforming our view of the Milky Way by turning stellar spectra into a fossil record of Galactic history to answer the big questions about our Milky Way Galaxy.

GALAH 2 now marks the next step: from mapping elements to precision Galactic Archaeology.

Instead of surveying as many stars as possible, GALAH 2 focuses on extracting the maximum physical information from stellar spectra to enable measurements precise enough to trace elemental enrichment patterns, stellar birth environments, characterise merger events, and connect stellar physics to galaxy evolution across cosmic time.

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Explore GALAH 2: Precision Galactic Archaeology

GALAH 2 combines:

• high-signal-to-noise multi-object spectroscopy with HERMES (≈350 stars per field, R≈30,000)
• ultra-high-precision single-object spectroscopy with Veloce (390–950 nm, R≈80,000)

to create a new calibration backbone for stellar spectroscopy across the Hertzsprung–Russell diagram. The programme is flexible and science-driven, including benchmark stars, stellar twins, and community-led target selection. These observations enable abundance measurements with unprecedented internal consistency and precision, allowing us to move beyond population trends toward reconstructing the detailed formation history of the Galaxy. Observations with Veloce are already underway, and the first reduced spectra are now being analysed.

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Want to start working right now with GALAH DR4?

The GALAH survey published our fourth data release on 1 October 2024. For 917,588 stars, we provide reduced spectra, stellar parameters and up to 31 elemental abundances.

If you want our best effort stellar parameters and elemental abundances, we recommend the galah_dr4_allstar_240705.fits catalogue.

Get GALAH DR4 catalogues
Get GALAH DR4 spectra
Read the DR4 documentation