In this paper, a novel ground station localization
algorithm is proposed for space optical communications using ar-
ray processing and a set of celestial objects of known locations in
the global coordinate system. First, the ground station estimates
the directions of this set of celestial objects relative to its local
coordinate system using the sunlight reflected by these celestial
objects. Then, the ranges of the celestial objects and the location
and orientation of the ground station are estimated by solving
systems of nonlinear and linear equations. The performance of
the proposed approach is assessed through computer simulation
studies. It is shown to estimate the location and orientation of
the ground station successfully with excellent accuracy.