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Selection of MOONS and 4MOST projects

» Thursday 21 July 2011

In September 2010, ESO made a Call for Letter of Intent for Wide-Field Spectroscopic Survey Facilities. In May 2011, ESO selected two phase A studies, among the seven submitted proposals:

  • MOONS,
  • 4MOST.

GEPI is involved in both these instruments.


Multi-Object Optical and Near-infrared Spectrograph

MOONS is a project for a multi-object spectrograph on the VLT. Its spectral coverage will range from 800 (ideally 500) to 1800 nm. The multiplex will be 250 (ideally 500) fibres allocated to objects and the same amount for blank sky positions. Two spectral resolutions will be available:
medium (3000-5000) and high resolution (20000). MOONS is a "GIRAFFE-like" instrument that will be able to share the positioner OzPoz from the FLAMES facility in UT2.

The science cases of the instrument are:

  • Galactic Archaeology (GAIA follow-up)
  • Cosmology and large-scale structures
  • Galaxy formation and evolution
  • First galaxies and re-ionization

The consortium is headed by UK-Astronomy Technology Center and Institute for Astronomy (Royal Observatory, Edinburgh) and gathers the Centre for Astro-Engineering at Universidad Catolica (Chile), GEPI, Max-Planck-Institut für extraterrestrische Physik (Germany), INAF (Italy) and NOVA - Nederlandse Onderzoekschool voor de Astronomie (Netherland).

GEPI is in charge of the fibre assembly and the data reduction software packages.

To learn more:


4-meter Multi-Object Spectroscopic Telescope

The project 4MOST aims at dedicating a telescope and multi-object spectrographs to spectroscopic surveys. These surveys will be carried on simultaneously in order to optimize multiplex and observing time. The 4MOST facility will be hosted on NTT or VISTA. A medium resolution spectrograph will be fed 1500 fibres (goal 3000) distributed over a 2° diameter field-of-view (goal 3°). Spectral resolution will be 3000 (goal 5000) in the blue: 420-650 nm (goal 380-650 nm) and 5000 (goal 7500)
in the red: 650-900 nm (goal 650-1000 nm). A high resolution spectrograph will be fed by 10-20% of the fibres and cover the spectral ranges 390-450 nm and 585-675 nm with a resolution > 20000.

The science cases of the facility are:

  • Gaia follow-up (radial velocities, atmospheric parameters, abundances)
  • eROSITA follow-up
  • Euclid (and other imaging surveys) follow-up

GEPI is in charge of the high resolution spectrograh.

The consortium is composed of:

Leading Institutes

  • Leibniz-Institut für Astrophysik Potsdam (Germany)
  • Ludwig-Maximilian Universität, München (Germany)
  • MPI für Extraterrestrische Physik, München (Germany)
  • GEPI

Supporting Institutes

  • ESO, Garching
  • Cambridge University (United Kingdom)
  • University of Oxford/RAL (United Kingdom)
  • NOVA, Dwingeloo (Netherland)
  • Zentrum für Astronomie, Univ. of Heidelberg (Germany)
  • Australian Astronomical Observatory (Australia)

Science Institutes

  • University of Groningen (Netherlands)
  • University of Lund (Sweden)
  • University of Uppsala (Sweden)