and Burkert models (Burkert 1995), because of the large scatter of data as well as for the limited radius within which the rotation curve is observed. Recent extensive observations of M31 showed that the rotation curve is similar to that of the Galaxy and can be decomposed into bulge, disk and an extended dark halo (Carignan et al. 2006).

Kinematics of satellites and member galaxies in the Local Group is a crew to estimate the dark halo, which is considered to be extended far outside the galactic disk and in the intracluster space. Kahn and Woltjer (1959) for the time argued for dark matter in the Local Group beyond the Galactic disk, obtaining a few $10^{12}\Msun$, by analyzing the motion of satellite galaxies. There have been many works to use satellite galaxies to probe the mass and density distribution around galaxies (e.g., Einasto, et al. 1974; Ostriker et al. 1974; Zaritsky et al. 1989, 1997; Fich and Tremaine 1991; Kochanek 1996; Kulessa and Lynden-Bell 1992; Peebles et al. 2001; Prada et al. 2003). Recently, Li and White (2007), and van der Marel and Guhathakurta (2008) analyzed the radial velocities of satellite galaxies surrounding the Galaxy and M31, deriving a total 