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In the past several years high resolution kinematic data sets from Milky Waysatellite galaxies have confirmed earlier indications that these systems aredark matter dominated objects. Further understanding of what these galaxiesreveal about cosmology and the small scale structure of dark matter relies inlarge part on a more detailed interpretation of their internal kinematics. Thisarticle discusses a likelihood formalism that extracts important quantitiesfrom the kinematic data, including the amplitude of rotation, proper motion,and the mass distribution. In the simplest model the projected error on therotational amplitude is shown to be $\sim 0.5 $ km s$^{-1}$ with $\sim 10^3$stars from either classical or ultra-faint satellites. The galaxy Sculptor isanalyzed for the presence of a rotational signal; no significant detection ofrotation is found, and given this result limits are derived on the Sculptorproper motion. A criteria for model selection is discussed that determines theparameters required to describe the dark matter halo density profiles and thestellar velocity anisotropy. Applied to four data sets with a wide range ofvelocities, the likelihood is found to be more sensitive to variations in theslope of the dark matter density profile than variations in the velocityanisotropy. Models with variable radial velocity anisotropy are shown to bepreferred relative to those in which this quantity is constant at all radii inthe galaxy.

Kinematics of Milky Way Satellites: Mass Estimates, Rotation Limits, and Proper Motions