First Results from an ESA Study on Accurate Orbit Determination with Laser Tracking of uncooperative Targets

Within the framework of ESA's General Support Technology Program (GSTP) the Project “Accurate Orbit Determination with Laser Tracking” was successfully launched at the end of 2014. The participating institutions comprise the German Aerospace Center, Institute of Technical Physics, Stuttgart, the Austrian Academy of Science, Space Research Institute, Graz, the Technical University Munich, Research Facility Satellite Geodesy, Munich and the Federal Office for Cartography and Geodesy, Geodetic Observatory, Wettzell. The scope of this project encompasses the establishment of new tracking techniques for uncooperative, space-borne targets: Simultaneous 2-way laser ranging from two sites at two laser wavelengths (Wettzell: 1064 nm; Graz: 532 nm); and simultaneously multi-static ranging, where the stations in Graz and Stuttgart detected the diffuse radiation of Wettzell, backscattered from the space debris targets. Results are presented unveiling the rotational behaviour of rocket bodies as well as improved accuracy of orbit predictions due to the multi-static observation geometry.
For laser ranging to uncooperative targets, the cross section of the smallest objects detected so far are about 0.5 m², and the largest distances are about 3000 km.