A 'compound eye' on the sky

At ESO's Very Large Telescope ( VLT ) in Chile they are about to fit a new instrument that can record the light from 24 galaxies simultaneously. KMOS has 24 robotic arms tipped with gold-plated mirrors that can be trained on a different galaxy - each arm has almost 200 facets making them rather like an insect's compound eye. Light from these mirrors is channelled into 3 spectrographs and 'multiplexed' - combined into a single signal. The 3 spectrographs were designed, manufactured, and assembled at Oxford University before being shipped out to Chile via STFC's UK Astronomy Technology Centre in Edinburgh. Working at infrared wavelengths, KMOS will probe a crucial time in the evolution of galaxies: around 10 billion years ago when star formation was at its height and the black holes believed to nestle in the centres of most galaxies were also highly active. 'Not only will KMOS accelerate the study of high redshift galaxies through the multiplex advantage, it will also provide a much more detailed view, allowing us to study gas flows and star forming regions in each individual galaxy,' Roger Davies, who led work at Oxford on the KMOS spectrographs, explains. 'We expect that these will reveal the connection between the evolution of the stars in galaxies and central black hole.