Patent ID: 7745768
Filing Date: 2010-06-29
Classification: B64G,G01S

Abstract:
1. An absolute target system comprising: a star sensor having a catalogue of stars listing a set of known bright stars, whose absolute accuracy is known, with a catalogue accuracy of the catalogue incorporated in the absolute target system, an optical metrological sensor to accurately determine relative positions of the bright stars, with a measurement accuracy with which is associated a frame of reference, said star sensor and said optical metrological sensor cooperating so that the star sensor can be used to roughly point the optical metrological sensor in a target direction corresponding to a known bright star in the star catalogue, the optical metrological sensor then accurately determining the direction of said known bright star in its own frame of reference, so making it possible to know a target direction with optimized absolute accuracy, corresponding approximately to a measurement accuracy of the optical metrological sensor, within tolerance of the catalogue accuracy.