The Shape of the Milky Way Halo and the Satellite Tidal Tails
  The dwarf galaxies orbiting a main galaxy suffer strong tidal forces produced by its dark halo. As a consequence, substructures and tidal tails could appear in the satellites. These structures could give us information about the dark matter content of the main and the dwarf galaxies. The Milky Way satellites, because of their proximity, are a good sample to study the effects of the tidal forces. The shape of the Milky Way potential could be inferred from the observational data of the tidal tails of its satellites. The Sagittarius dwarf is one of the most interesting satellites as it presents a long tidal tail that covers a wide angle on the sky with a large variation of heliocentric distance along the stream. 
M.A. G\'omez-Flechoso (Universidad Europea de Madrid)