Space Debris Observation Using Star Sensors Based on Scanning Circle Model

With the large-scale deployment of mega-constellations, the number of on-orbit star sensors is rapidly increasing. Building on the advancements in star sensor detection capabilities, this paper proposes utilizing star sensors as dual-purpose sensors to observe space debris while fulfilling their primary task of attitude determination. A scanning circle (SC) model is established to analyze the observation performance of the space debris located in the Geostationary Earth Orbit (GEO) belt region using star sensors. Based on this model, the optimal optical axis installation orientation of star sensors is derived to ensure full coverage of the GEO belt. Taking a star sensor onboard a sun-synchronous orbit (SSO) satellite at an altitude of 700 km as an example, it is demonstrated that setting the installation pitch angle at 13.8° and azimuth angle at 21.2° enables approximately full coverage of the GEO belt through 10 days of long-term observation. Furthermore, by expanding the single star sensor SC model, this paper proposes using star sensors onboard distributed satellite platforms to enhance observation efficiency. The results indicate that deploying 5 star sensors on distributed platforms can achieve rapid full-coverage of the GEO belt within 24 hours. The proposed strategy of using star sensors for space debris observation and the SC model not only expand the application of star sensors into the field of space situational awareness but also open up broader commercial prospects.