Methods and Apparatus for Navigational Aiding Using Celestial Object Tracking

Methods and computer products for establishing at least one of attitude, direction and position of a moving platform. At least one skymark of known ephemeris is imaged at each of a first set of discrete instants by means of an optical sensor coupled to the platform. A measurement is also obtained of the attitude of the platform at each of a second set of discrete instants by means of an inertial navigation system. A recursive of estimation filter is then applied to successive skymark position vectors to update an estimate of platform navigation state, with the measurement of attitude of the platform tightly coupled to the estimate of platform navigation state as updated by the recursive estimation filter. Various techniques of frame stacking and multi-hypothesis tracking may be applied to improve the robustness of navigation solutions.