The 4MOST Survey of Dwarf Galaxies and their Stellar Streams (4DWARFS)

The present-day Milky Way is the result of a long history of mergers and interactions with smaller galaxies. The 4DWARFS survey will target the dwarf galaxies and stellar streams in the 4MOST footprint, and unveil their chrono-chemo-kinematical properties. The survey will provide radial velocities, chemical abundances and stellar ages for 140 000 stars, and thus increase the number of stars with detailed information in such systems by several orders of magnitude. 4DWARFS will provide a new, deeper view of the Milky Way environment, shedding light on the first stars, chemical evolution, dark matter halos, and hierarchical galaxy formation down to the smallest scales.