What can Gaia proper motions tell us about Milky Way dwarf galaxies?
  We present a proper-motion study on models of the dwarf spheroidal galaxy
Sculptor, based on the predicted proper-motion accuracy of Gaia measurements.
Gaia will measure proper motions of several hundreds of stars for a
Sculptor-like system. Even with an uncertainty on the proper motion of order
1.5 times the size of an individual proper-motion value of ~10 mas/century, we
find that it is possible to recover Sculptor's systemic proper motion at its
distance of 79 kpc.
