The Future of Multi-Object Spectroscopy: a ESO Working Group Report

Understand

(Abridged) We consider the scientific case for a large aperture (10-12m class) optical spectroscopic survey telescope with a field of view comparable to that of LSST.

• Such a facility could enable transformational progress in several areas of astrophysics, and may constitute an unmatched capability for decades.
• Deep imaging from LSST and Euclid will provide accurate photometry for spectroscopic targets beyond the reach of 4m class instruments.
• Such a facility would revolutionise our understanding of the assembly and enrichment history of the Milky Way and the role of dark matter through chemo-dynamical studies of tens of millions of stars in the Local Group.