Detecting Halo Streams with GAIA
  We investigate what the proposed ESA astrometric satellite GAIA will reveal by observing the halo of the Milky Way. Specifically, we look for halo streams which are the signatures left by the merging/accretion events experienced by a typical galaxy like the Milky Way. We run numerical simulations of the disruption of satellite galaxies in a Galactic potential to generate artificial GAIA halo catalogs. We recover the streams by searching for peaks in angular momentum space. 
Amina Helmi, HongSheng Zhao and P. Tim de Zeeuw (Sterrewacht Leiden)