Mapping the Local Group
Kathryn Johnston (Columbia)
In the last decade, the stellar halos of the Milky Way and Andromeda
galaxies have been mapped in exquisite detail, revealing abundant
substructure and many new satellites. These observations are
qualitatively consistent with our expectations for large galaxies
formed hierarchically from smaller galaxies, but are they actually
telling us anything more quantifiable? In this talk I will review the
origin of these substructures, discuss how they can be mapped and
discuss possible interpretations.