Gravitational Focusing of Low-Velocity Dark Matter on the Earth's
  Surface
  We show that the Earth acts as a high-efficiency gravitational collector of
low-velocity flow of dark matter (DM). The focal point appears on the Earth's
surface, when the DM flow speed is about 17 km/s with respect to the
geo-center. We discuss diurnal modulation of the local DM density influenced by
the Earth's gravity. We also touch upon similar effects on galactic and solar
system objects.
