  The Cauchy problem of the bipolar Navier-Stokes-Poisson system (1.1) in
dimension three is considered. We obtain the pointwise estimates of the
time-asymptotic shape of the solution, which exhibit generalized Huygens'
principle as the Navier-Stokes system. This phenomenon is the the most
important difference from the unipolar Navier-Stokes-Poisson system. Due to
non-conservative structure of the system (1.1) and interplay of two carriers
which counteracts the influence of electric field (a nonlocal term), some new
observations are essential for the proof. We make full use of the conservative
structure of the system for the total density and total momentum, and the
mechanism of the linearized unipolar Navier-Stokes-Poisson system together with
the special form of the nonlinear terms in the system for the difference of
densities and the difference of momentums. Lastly, as a byproduct, we extend
the usual $L^2(\mathbb{R}^3)$-decay rate to $L^p(\mathbb{R}^3)$-decay rate with
$p>1$ and also improve former decay rates in part.
