Dynamical Masses for a Complete Census of Local Dwarf Galaxies
  The 2020s are poised to continue the past two decades of significant advances
based on observations of dwarf galaxies in the nearby universe. Upcoming
wide-field photometric surveys will probe substantially deeper than previous
data sets, pushing the discovery frontier for new dwarf galaxies to fainter
magnitudes, lower surface brightnesses, and larger distances. These dwarfs will
be compelling targets for testing models of galaxy formation and cosmology,
including the properties of dark matter and possible modifications to gravity.
However, most of the science that can be extracted from nearby dwarf galaxies
relies on spectroscopy with large telescopes. We suggest that maximizing the
scientific impact of near-future imaging surveys will require both major
spectroscopic surveys on 6-10m telescopes and multiplexed spectroscopy with
even larger apertures.
