Laser-based monitoring and removal of space debris

Owing to the extended use of space since the first launch of a satellite in 1957, an increasing number of remnants of on-orbit collisions, explosions and defunct satellites are circulating at high population density on important LEO and GEO orbits. Due to the velocities of these objects, even small particles impose significant risk for space assets. While larger LEO objects are permanently tracked by radar, barely any information is available on the orbits of objects at a size range of 1 cm to 10 cm. Hence, an effective and precise determination of exact orbital data is a prerequisite for collision risk mitigation and future removal approaches. In this talk, the concept of a laser-based monitoring system for LEO space debris will be presented and the feasibility of space debris removal employing high energy lasers will be discussed. Such a monitoring system offers various advantages and complements the current state-of-the-art detection with radar systems and passive optical observation. All parameters influencing the detection approach are considered, including the propagation of laser beams through turbulent atmosphere, scattering characteristics of the debris objects, and the required pulse energy of the laser used for time-of-flight ranging. These system parameters will be verified by scaled on-ground experiments. Our development goal is a monitoring platform including a 1 kHz repetition rate laser of 1 J pulse energy, which allows for the demonstration of technical feasibility of the discussed approach and stimulates further activities