The Science and the Survey

The complete PAndAS survey area covers a total of approximately 350 square degrees on the sky, covering the halo of M31 (Andromeda) out to a maximum projected radius of 150 kpc (a diameter of nearly 1,000,000 light years!) and the halo of the smaller M33 (Triangulum) out to a maximum projected radius of 50 kpc. PAndAS will therefore probe the haloes of these galaxies over a volume of roughly 15 million cupic kiloparsecs, reaching limiting magnitudes of roughly g = 25.5 and i = 24.5, sufficient to detect structure to a limiting surface brightness of 32 - 33 mags per square arcsec.

PAndAS: the survey

The survey area and the constituent fields are shown opposite, overlaid on a map of Galactic foreground extinction from the study of Schlegel et al. (1998). The blue outline shows the position of our extant imaging of the south-east quadrant (first results presented in Martin et al. 2006, Ibata et al. 2007), and the hatched green fields shows imaging of the south-west quadrant (first results presented in McConnachie et al. 2008). Also shown are the positions of some of the satellites of M31, including distant globulars and several recently discovered dwarf galaxies.