Hypervelocity Stars and the Galactic Center
  A summary of the current knowledge on hypervelocity stars (HVSs). HVSs are fascinating because their properties are linked to Sgr A* and the stellar environment of the Galactic Center. Observing the distribution of HVSs can address: 1) the nature of the black hole ejection mechanism, 2) the in-fall history of stars onto Sgr A*, 3) the types of stars orbiting Sgr A*, and 4) a unique measurement the shape of the Galaxy's dark matter potential. The challenge to observers is to find new HVSs and strengthen the connection between HVSs and the Galactic Center. 
Warren R. Brown (Smithsonian Astrophysical Observatory)