  The charge of microparticles immersed in the dc discharge of the
Plasmakristall-4 experimental facility has been estimated using the particle
velocities from experiments performed on Earth and under microgravity
conditions on the International Space Station. The theoretical model used for
these estimates is based on the balance of the forces acting on a single
particle in the discharge. The model takes into account the radial dependence
of the discharge parameters and describes reasonably well the experimental
measurements.
