European
Southern
Observatory

ELT Instruments
HIRES
HIgh REsolution Spectrograph

The high-resolution ELT instrument HIRES will allow astronomers to study astronomical objects that require highly sensitive observations. It will be used to 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.

In a nutshell

The high-resolution ELT instrument HIRES will allow astronomers to study astronomical objects that require highly sensitive observations. It will be used to 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.

HIgh REsolution Spectrograph

The high-resolution ELT instrument HIRES will allow astronomers to study astronomical objects that require highly sensitive observations. It will be used to 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.

As a powerful spectrograph, HIRES will split up light from astronomical targets into all its component wavelengths, enabling astronomers to study a wide range of wavelengths in high-resolution. This second-phase ELT instrument will combine its high resolution and wide spectral range with the huge surface area of the ELT to produce data with exquisite detail and sensitivity.

The high-resolution data collected by the instrument will enable astronomers to research an unprecedented range of topics spanning most areas of astrophysics and even breaking into the domain of fundamental physics. HIRES has the potential to greatly impact our understanding of the cosmos and its fate.

Science with HIRES

HIRES has a broad range of science cases. Some of its most outstanding scientific goals include characterising the atmosphere of Earth-like exoplanets—with the ultimate goal of detecting signatures of life—identifying the very first generation of stars, studying possible variations in some of the fundamental constants of physics, and directly measuring the acceleration of the Universe's expansion.

Thanks to the ELT's enormous main mirror, HIRES 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 HIRES 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. HIRES will also be able to observe forming protoplanets and their impact on the natal protoplanetary disc.

Moving much further from Earth, HIRES 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, HIRES 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, HIRES will provide the most accurate tests of the fine-structure constant and the electron-to-proton mass ratio. Furthermore, HIRES 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.

Instrument Design

The HIRES baseline design is that of a modular fibre-fed cross dispersed echelle spectrograph which has two ultra-stable spectral arms, visual and near-infrared, providing a simultaneous spectral range of 0.4 -1.8 μm at a spectral resolving power of R~100,000 for a single object.  HIRES will also include an IFU mode fed by a single-conjugate adaptive optics (SCAO) module to correct for the blurring effect of turbulence in the atmosphere. 

HIRES 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.

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

Wavelength

0.55—1.80 μm (baseline), 0.33—2.44 μm (goal)

Spectral resolution

100,000 − 150,000

Field(s)-of-view

0.170'', 64 fibres (R ~ 100,000), 0.113'', 96 fibres (R ~ 150,000) 

Tools and Documents

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, as initially submitted by the Instrument Consortium 

Top Level Requirements

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

Instrument Consortium and Contacts

The HIRES project is managed by an international consortium composed of research institutes from twelve different countries. 

HIRES is being designed and built under the leadership of the Italian National Institute for Astrophysics by partners in Brazil, Chile, Denmark, France, Germany, Italy, Poland, Portugal, Spain, Sweden, Switzerland, United Kingdom. The consortium consists of the Board of Observational Astronomy at the Federal University of Rio Grande do Norte (Brazil), the Mauá Institute of Technology (Brazil), the Centre of Astro Engineering at the Pontifical Catholic University of Chile (Chile), the Department of Astronomy at the University of Chile (Chile), the Center of Astronomical Instrumentation at the University of Concepción (Chile), the Astronomy Center at the University of Antofagasta (Chile), the Niels Bohr Institute at the University of Copenhagen (Denmark), the Institute of Physics and Astronomy at the University of Aarhus (Denmark), the Marseille Astrophysics Laboratory (France), the Grenoble Institute for Planetary Sciences and Astrophysics (France), the Lagrange Laboratory at the Côte d’Azur Observatory (France), the Leibniz Institute for Astrophysics Potsdam (Germany), the Institute for Astrophysics at the University of Göttingen (Germany), the Center for Astronomy at Heidelberg University (Germany), Thuringian State Observatory (Germany), Hamburg Observatory at the University of Hamburg (Germany), the Faculty of Physics, Astronomy and Informatics at the Nicolaus Copernicus University in Toruń (Poland), the Institute of Astrophysics and Space Sciences at the Universities of Porto and Lisbon (Portugal), the Institute of Astrophysics of the Canary Islands (Spain), the Institute of Astrophysics of Andalusia (Spain), the Astrobiology Center (Spain), the Department of Physics and Astronomy at Uppsala University (Sweden), the Department of Astronomy at the University of Geneva (Switzerland), the Physics Institute at the University of Bern (Switzerland), the Cavendish Laboratory at the University of Cambridge (UK), the Institute of Astronomy at the University of Cambridge (UK), the UK Astronomy Technology Centre (UK), the Centre for Advanced Instrumentation at Durham University (UK), the Institute of Photonics and Quantum Sciences in the School of Engineering and Physical Sciences at Heriot-Watt University (UK).

Principal Investigator

Alessandro Marconi (University of Florence, Italy)

Project Scientist

Roberto Maiolino (University of Cambridge, UK)

Project Manager

Luca Valenziano (INAF Bologna, Italy)

ESO Project Manager

Frédéric Derie

ESO Project Scientist

Celine Peroux

ESO Project Engineer

Oliver Pfuhl