An investigation of planetary nebulae accompanying PG1159 central stars,
  based on Gaia DR2 measurements
  This article discusses the physical and kinematical characteristics of
planetary nebulae accompanying PG1159 central stars. The study is based on the
parallax and proper motion measurements recently offered by Gaia space mission.
Two approaches were used to investigate the kinematical properties of the
sample. The results revealed that most of the studied nebulae arise from
progenitor stars of mass range; $0.9-1.75$\,M$_{\odot}$. Furthermore, they tend
to live within the Galactic thick-disk and moving with an average peculiar
velocity of $61.7\pm19.2$\,km\,s$^{-1}$ at a mean vertical height of $469\pm79$
pc. The locations of the PG1159 stars on the H-R diagram indicate that they
have an average final stellar mass and evolutionary age of
$0.58\pm0.08$\,M$_{\odot}$ and $25.5\pm5.3 \rm{x}10^3$ yr, respectively. We
found a good agreement between the mean evolutionary age of the PG1159 stars
and the mean dynamical age of their companion planetary nebulae ($28.0\pm6.4
\rm{x}10^3$ yr).
