Study of Laser-Matter Interaction and Preliminary Design of a Space-Based Laser Ablation System for Active Space Debris Removal

The issue of space debris is becoming increasingly critical as Earth’s orbits grow more congested due to the rapid expansion of space activities. The Low Earth Orbit (LEO) and Geosynchronous Orbit (GEO) regions, due to their immense commercial and strategic importance, are the most intensively utilized. In response to this growing concern, the Inter-Agency Space Debris Coordination Committee (IADC) has designated these regions as "Protected Regions" and introduced mitigation measures, including post-mission disposal regulations. However, despite these efforts, debris accumulation continues, particularly in the LEO region, which is estimated to contain around 900,000 objects ranging from 1 cm to 10 cm in size—large enough to penetrate shielding but too small to be effectively tracked. These objects pose a significant threat to operational spacecraft, as their high-velocity impacts can cause catastrophic fragmentation, potentially triggering the Kessler Syndrome—a cascading chain reaction of collisions that exponentially increases the number of debris objects in orbit. Current mitigation strategies, such as end-of-life deorbiting and graveyard orbit transfers, have proven inadequate in slowing the growth of space debris. Consequently, active debris removal (ADR) has become a key area of research. Among the various ADR techniques under investigation, laser ablation stands out as a promising solution allowing the exertion of forces on debris remotely, without direct contact. When a high-energy pulsed laser irradiates the surface of a debris object, it induces the emission of a plasma plume. The resulting recoil force alters the debris' trajectory. This thesis investigates the laser ablation technique with the goal of defining the requirements for a laser payload in a satellite constellation dedicated to active space debris removal. The laser operates in a pulsed regime, with a pulse duration in the nanosecond range. Following an initial study of laser beam propagation over a target distance of approximately 100 km, the interaction between the laser and the debris surface is analyzed by modeling the energy transfer processes, accounting for losses due to radiation, vaporization, and thermal conduction into the material. To further investigate the debris thermal response, a 3D heat conduction model is developed using geometries representative of common debris, such as spheres and flat plates, and materials frequently found in space debris, including aluminum, copper, titanium, and silica. This model allows the evaluation of the ablation area and the forces exerted on the debris surface. Finally, a preliminary sizing of the satellite’s power system is conducted and its feasibility in meeting the energy demands of the laser payload is evaluated, considering potential constraints on power generation and spacecraft design. The results provide insight into the efficiency of laser ablation for ADR and help define system-level constraints for future laser-based debris removal missions.