Optical Observations in a Proposed European Space Surveillance Network

Space surveillance activities in Europe currently strongly depend on external sources. A limited number of European radar and optical facilities for space surveillance exist, but there is no operational European space surveillance system. Currently, ESA-funded feasibility studies awarded to ONERA are carried out to design a European Space Surveillance System. The system is proposed to consist of two subsystems, a phased-array radar system and a network of ground-based optical telescopes. The Astronomical Institute of the University of Bern (AIUB), Switzerland, contributes to the design of the optical observation part of the system, which is intended to cover the geostationary orbit (GEO) and the medium Earth orbit (MEO) regions. The developed observation strategy and the proposed preliminary sensor architecture will allow establishing and maintaining a catalogue of orbital parameters, and provide additional space surveillance functionalities such as fragmentation event identification, manoeuvre detection, new launch detection, and collision risk assessment. The paper will present the most important system requirements ,and the surveillance strategies for GEO and MEO, and will give an outline of the proposed optical sensor and network architecture. The expected performance of the proposed strategy, considering the preliminary sensor characteristics, will be discussed in terms of coverage of a reference population and in terms of minimum detectable object size. The performance assessment concludes with a validation of the algorithms to build up and maintain the catalogue, using observations acquired with ESA’s Space Debris Telescope at Tenerife, Spain.