Thanks to the ELT's enormous main mirror, ANDES will be able to explore and characterise planets outside of our Solar System. After decades of detecting exoplanets, the focus is now on observing and quantifying their atmospheres; the ultimate goal is to detect signatures of life. The unprecedented capabilities of ANDES will enable astronomers to investigate the chemical composition, layers, and weather in the atmospheres of many different types of exo-planets, from Neptune-like to Earth-like, including those in stars' habitable zones. ANDES will also be able to observe forming protoplanets and their impact on the natal protoplanetary disc.

Moving much further from Earth, ANDES is likely to be the first instrument to unambiguously detect the fingerprints of the first generation of stars (“population III” stars) that lit up the primordial Universe. This will be achieved by measuring the relative abundance of various chemical elements in the intergalactic medium in the early Universe and by detecting the chemical enrichment pattern typical of the first supernova explosions. 

Beyond astronomy, ANDES will reach into the territory of fundamental physics. It will help astronomers determine whether some of the fundamental constants of physics, which regulate most physical processes in the Universe, could actually change with time or space. In particular, ANDES will provide the most accurate tests of the fine-structure constant and the electron-to-proton mass ratio. Furthermore, ANDES will be used to directly measure the acceleration of the Universe’s expansion; such a measurement would greatly impact our understanding of the Universe and its fate.

ANDES will separate light from the ELT mirrors into two-wavelength channels using dichroic filters. Each wavelength channel interfaces with several fibre bundles that feed the corresponding spectrograph module (visual and near-infrared). Each fibre-bundle corresponds to an observing mode. All spectrometer modules have a fixed configuration, i.e. no moving parts. They include a series of parallel entrance slits consisting of linear micro-lense arrays each glued to the fibre bundles.

ANDES has completed the initial project stage known as Phase A. 

Exposure Time Calculator 

Tool to predict the exposure time needed to study an object with the instrument, for set environmental conditions 

Science Case

Description of the scientific motivations for the instrument 

Top Level Requirements

Description of the characteristics of the instrument required by the science case 

The ANDES project is developed by an International Consortium composed by Research Institutes of 13 Countries. Brazil: Board of Stellar Observational Astronomy, Universidade Federal do Rio Grande do Norte. Canada: Observatoire du Mont-Mégantic and the Trottier Institute for Research on Exoplanets, Université de Montréal. Denmark: Instrument Centre for Danish Astrophysics on behalf of Niels Bohr Institute, Aarhus University, Danmarks Tekniske Universitet. France: Centre National de la Recherche Scientifique (CNRS) on behalf of Observatoire de la Côte d’Azur, Université Côte d’Azur (LAGRANGE), Laboratoire d’Astrophysique de Marseille, Aix-Marseille Université, Centre National d’Etudes Spatiales (LAM), Institut de Recherche en Astrophysique et Planetologie, Université Toulouse III-Paul Sabatier (IRAP), Institut de Planétologie et d’Astrophysique de Grenoble, Université Grenoble-Alpes (IPAG), Laboratoire Univers et Particules de Montpellier, Université de Montpellier (LUPM), Institut d’Astrophysique de Paris, Sorbonne Université (IAP), Laboratoire de Météorologie Dynamique, Ecole Normale Supérieure, Ecole Polytechnique, Sorbonne Université (LMD). Germany: Leibniz-Institut für Astrophysik Potsdam (AIP), Institut für Astrophysik und Geophysik, Georg-August-Universität Göttingen (IAG), Atmospheric Physics of Exoplanets Department, Max-Planck-Institut für Astronomie Heidelberg (MPIA), Zentrum für Astronomie, Universität Heidelberg (ZAH), Thüringer Landessternwarte Tautenburg (TLS), Hamburger Sternwarte, Universität Hamburg (UHH). Italy: INAF, Istituto Nazionale di Astrofisica (Lead Technical Institute). Poland: Nicolaus Copernicus University in Torun. Portugal: Instituto de Astrofísica e Ciências do Espaço (IA) at Centro de Investigaço em Astronomia/Astrofísica da Universidade do Porto (CAUP), Instituto de Astrofísica e Ciências do Espaço at Faculdade de Ciências da Universidade de Lisboa, Associação para a Investigação e Desenvolvimento de Ciências (FCiências.ID). Spain: Instituto de Astrofísica de Canarias (IAC); Consejo Superior de Investigaciones Científicas (CSIC, Spain) on behalf of Instituto de Astrofísica de Andalucía (IAA), Centro de Astrobiología de Madrid (CSIC-INTA). Sweden: Lund University, Stockholm University, Uppsala University. Switzerland: Département d’Astronomie, Université de Genève; Weltraumforschung und Planetologie, Physikalisches Institut, Universität Bern. United Kingdom: Science and Technology Facilities Council, United Kingdom Research and Innovation on behalf of Cavendish Laboratory & Institute of Astronomy, University of Cambridge; UK Astronomy Technology Centre; Institute of Photonics and Quantum Sciences, Heriot-Watt University. USA: Department of Astronomy, University of Michigan.