MOSAIC on the ELT: high-multiplex spectroscopy to unravel the physics of
  stars and galaxies from the dark ages to the present-day
  The powerful combination of the cutting-edge multi-object spectrograph MOSAIC
with the world largest telescope, the ELT, will allow us to probe deeper into
the Universe than was possible. MOSAIC is an extremely efficient instrument in
providing spectra for the numerous faint sources in the Universe, including the
very first galaxies and sources of cosmic reionization. MOSAIC has a high
multiplex in the NIR and in the VIS, in addition to multi-Integral Field Units
(Multi-IFUs) in NIR. As such it is perfectly suited to carry out an inventory
of dark matter (from rotation curves) and baryons in the cool-warm gas phases
in galactic haloes at z=3-4. MOSAIC will enable detailed maps of the
intergalactic medium at z=3, the evolutionary history of dwarf galaxies during
a Hubble time, the chemistry directly measured from stars up to several Mpc.
Finally, it will measure all faint features seen in cluster gravitational
lenses or in streams surrounding nearby galactic halos, providing MOSAIC to be
a powerful instrument with an extremely large space of discoveries. The
preliminary design of MOSAIC is expected to begin next year, and its level of
readiness is already high, given the instrumental studies made by the team.
