I am a member of the Pan-Andromeda Archaeological Survey (PAndAS) collaboration. This survey has mapped the Andromeda galaxy from its central bulge and disk, out to 150 kpc into its stellar halo, using the Canada France Hawaii telescope.
My role in this team has been to acquire and analyse follow up spectroscopy of individual stars within this galaxy, and its dwarf satellites. To do this, I have used the Keck II telescope and the DEIMOS spectrograph. Using these spectra, we can determine the amount of dark matter within Andromeda and its satellites, and us this information to learn more about this mysterious stuff which makes up ~25% of the Universe. We can also learn about the chemicals contained within these stars, which allows us to learn about how and when they formed, giving us detailed insight into the evolution of a massive spiral galaxy system.
I am also involved in deep, wide-field imaging of nearby galaxies, and studies of Milky Way dwarf galaxies.