Jan Siminski (DLR / GSOC), Martin Weigel (Scientist, Space Situational Awareness group), Hauke Fiedler (Head Space Situational Awareness group)
Keywords: Space situational awareness, Initial orbit determination, Catalog build-up, Too-short-arcs, Tracklet association
Abstract:
In order to guarantee save operation of satellites in the geostationary orbit, space object databases are created. Close encounters between uncontrollable and active objects must be detected and maneuvers must be planned to avoid future collisions. The geostationary orbit is typically monitored using ground-based optical telescopes. They are operated in a surveillance mode, i.e. the entire region is covered by the observation strategy to ensure a complete catalog. Due to limited resources, objects can only be observed for short durations. The resulting measurement arcs, called tracklets, do not provide enough information to determine the full state of the objects. When building up the database using no prior information, tracklets must be associated to each other to obtain object candidates. An efficient method was developed for this task, which optimally uses the information contained in the short sequences of angular measurements, i.e. the line-of-sights and their derivative. The resulting candidate solutions are either confirmed and refined with further observations or rejected. This work will examine whether it is feasible to build up a catalog using the developed algorithms and short tracklets as observations. A simulation of an optical sensor network is performed. Near-geostationary objects are extracted from publicly available catalogs. The developed method is then used to generate the catalog. The resulting object database is analyzed for accuracy and completeness. The study will outline the performance of such a system and identify deficiencies.
Date of Conference: September 9-12, 2014
Track: Astrodynamics