Orbital masses of nearby luminous galaxies
  We use observational properties of galaxies accumulated in the Updated Nearby
Galaxy Catalog to derive a dark matter mass of luminous galaxies via motions of
their companions. The data on orbital-to-stellar mass ratio are presented for
15 luminous galaxies situated within 11 Mpc from us: the Milky Way, M31, M81,
NGC5128, IC342, NGC253, NGC4736, NGC5236, NGC6946, M101, NGC4258, NGC4594,
NGC3115, NGC3627 and NGC3368, as well as for a composit suite around other
nearby galaxies of moderate and low luminosity. The typical ratio for them is
M_{orb}/M* = 31, corresponding to the mean local density of matter Omega_m =
0.09, i.e 1/3 of the global cosmic density. This quantity seems to be rather an
upper limit of dark matter density, since the peripheric population of the
suites may suffer from the presence of fictitious unbound members. We notice
that the Milky Way and M31 haloes have lower dimensions and lower stellar
masses than those of other 13 nearby luminous galaxies. However, the
dark-to-stellar mass ratio for both the Milky Way and M31 is the typical one
for other neighboring luminous galaxies. The distortion in the Hubble flow,
observed around the Local Group and five other neighboring groups yields their
total masses within the radius of zero velocity surface,R_0, which are slightly
lower than the orbital and virial values. This difference may be due to the
effect of dark energy, producing a kind of "mass defect" within R_0.
