The increasing congestion of Low Earth Orbit (LEO), with on the order of ten thousand active satellites and several tens of thousands of tracked resident space objects, requires improved tracking capabilities to support Space Domain Awareness (SDA) and Space Traffic Management (STM) operations.

This work presents the performance assessment of two dedicated LEO optical tracking telescopes, installed in Portugal and Chile. The twin telescopes employ fast optics, high-sensitivity cameras and precise time-tagging to provide high-accuracy astrometric measurements suitable for applications that require precise orbit determination and have been integrated into an operational SDA/STM platform.

The study focuses on laser calibration targets (e.g. LARES, STARLETTE) and cooperative satellites (e.g. Sentinel?6) followed by International Laser Ranging Service (ILRS), spanning altitudes of approximately 650–1400 km and inclinations above 50°.

Observation data collected over several weeks are first analysed at measurement level to characterise timing biases, residuals, fit quality, and the ratio of usable observations. These measurements are then used in a batch least-squares orbit determination process, from which position and velocity errors are quantified with respect to orbits derived from high-accuracy ILRS CPF products. The impact of combining measurements from both geographically separated sensors is examined in terms of reduction of systematic errors and overall orbit-determination accuracy.

Results show that the dual-telescope network achieves angular accuracies at the arcsecond level with small and stable timing biases, enabling high-quality orbit determination for the analysed satellites. Maximum position errors over one orbital revolution of propagated orbits are found to be on the order of a few hundred metres when using data from a single site, and are significantly reduced when combining data from both telescopes. These findings demonstrate that these data can be used to augment existing tracking infrastructures and to contribute to near-real-time collision risk assessment within an operational SDA/STM framework, and they highlight the potential of small networks of dedicated LEO optical sensors to support safe operations, in particular for higher-altitude LEO orbits.