ELT Instrument News: HIRES is now ANDES; MOSAIC Also Moving Forward

Published: 10 Mar 2022

ANDES is the new name for the high-resolution spectrograph, formerly known as HIRES, for the Extremely Large Telescope (ELT). Another instrument dubbed HIRES is successfully operating on the Keck telescope, so it was decided to rename the ELT spectrograph. Through an open process, the consortium — in consultation with the ESO follow-up team — has decided on "ArmazoNes high Dispersion Echelle Spectrograph", or ANDES. The official start of both ANDES and MOSAIC as two more ELT instrument projects was approved by the ESO Council in December last year.

ANDES is a multi-purpose spectrograph providing simultaneous observing modes from visible to near-infrared wavelengths with extraordinary high-resolution. It will search for signs of life in Earth-like exoplanets, find the first stars born in the Universe, test for possible variations of the fundamental constants of physics, and measure the acceleration of the Universe's expansion.

MOSAIC is a versatile multi-object spectrograph that will use the widest possible field-of-view provided by the ELT. It will provide the ability to study the spectral properties with intermediate and high spectral resolution of hundreds of objects in one pointing, as well as study their kinematics and diffuse gas emission in a spatially resolved fashion using several Integral Field Units. The scientific scope of MOSAIC is vast and covers many science topics from understanding the formation and evolution of our own Galaxy, to galaxy evolution across cosmic time up to the epoch of reionisation at z>7, to the study of dark matter and the inventory of baryonic matter.