Abstract: A control system and method that keeps solar arrays on a satellite pointing toward the sun. Exemplary control systems and methods are implemented as follows. An orbit propagator computes satellite orbital location data and computes a sun vector referenced to an inertial reference frame. A coordinate transformation processor processes the sun vector in the inertial reference frame and a sensed satellite attitude signal to generate a sun vector referenced to a satellite body reference frame. A solar array position processor processes a step count derived from a solar array pointing control system and sensed solar array position to generate an estimate of the position of the solar array. A summing device sums the solar array position estimate output, the body frame gun vector, and a bias signal derived from a ground command, to produce a solar array position error signal. A filter filters the solar array position error signal.