  The aim of this work is to prove the weak-strong uniqueness principle for the
compressible Navier-Stokes-Poisson system on an exterior domain, with an
isentropic pressure of the type $p(\varrho)=a\varrho^{\gamma}$ and allowing the
density to be close or equal to zero. In particular, the result will be first
obtained for an adiabatic exponent $\gamma \in [9/5,2]$ and afterwards, this
range will be slightly enlarged via pressure estimates "up to the boundary",
deduced relaying on boundedness of a proper singular integral operator.
