HERMES is a multi-object spectrograph commissioned at the Anglo-Australian Telescope (AAT) in 2014 that covers four optical bands simultaneously at a spectral resolution of ~28,000. The HERMES instrument is driven primary by the ‘Galactic Archaeology’ science project, which aims to reconstruct the history of our Galaxy’s formation from precise multi-element abundances of 1 million stars.
The HERMES spectrograph is fed by 396 fibres from the AAT’s existing 2dF optical fibre positioner. It uses a reflective collimator with four transmissive camera channels. All channels use large format mosaiced volume phase holographic gratings at high Lithrow angle. The spectrograph has a relatively large beam diameter of 200 mm.