The growing interest in low-altitude operations for scientific and commercial applications has strengthened the relevance of orbit-lowering campaigns in Low Earth Orbit (LEO). Operating in this environment offers substantial advantages, including enhanced spatial resolution for Earth observation and natural compliance with space debris mitigation guidelines. However, the significant atmospheric drag and strong coupling between orbital and aerodynamic dynamics make trajectory optimization a complex task. This work addresses the problem of optimizing a low-thrust orbital descent using an indirect approach based on Optimal Control Theory (OCT). The governing equations are formulated as a Two-Point Boundary Value Problem (TPBVP), derived from the necessary conditions of optimality given by Pontryagin’s Maximum Principle.