The hierarchical growth scenario has
emerged at the dominant theory for galaxy evolution. Whilst the
general picture has reached a consensus, the next crucial step it is
to identify and then analyse the signatures of this accretion. Rapid
progress has been made in recent years thanks to modern large-scale
surveys that have been mapping vast portions of the sky, recording a
wealth of information on many millions of stars in the Milky Way. Such
large databases have allowed researchers to identify accretion
remnants at a startling pace, increasing the number of known Milky Way
dSph companions by a factor of ~2 in the past three years alone. I
will review the work that has been undertaken at the IoA in Cambridge,
covering the numerous satellites, streams and structures that have
been discovered with SDSS/SEGUE. These data have allowed us to extend
the search for Milky Way satellites down to surface-brightness
unreachable with previous surveys. The resulting ultra-low luminosity
objects have important implications for our understanding of dark
matter and galaxy formation on the smallest scales, while the
discovery of streams can tell us about the formation and composition
of the Milky Way halo. I will discuss the extensive follow-up work
that has been carried out in order to better understand these new
Milky Way satellites/structures and present the latest findings that
have been made in recent months. Furthermore, I will describe new
efforts to probe halo assembly through velocity space signatures using
SEGUE spectra.
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