A system (18) includes: a) A vehicle (12) includes an attitude or angular
velocity control system (38), a plurality of star trackers or star
sensors (22) each having a field of view (28); b) a memory (30) having a
star catalog (32), a star pair catalog (58) and a reference table (56)
stored therein; and c) a processor (24) coupled to the attitude or
angular velocity control system (38), the star trackers or star sensors
(22), and the memory (30). The processor (24) determines the vehicle
inertial attitude or angular velocity or sensor alignment, based, in
part, on the star pair catalog (58) and reference table (56). The design
of the star pair catalog (58) and reference table (56) is suitable for
rapid determination of attitude or angular velocity or sensor alignment,
and an efficient use of memory.