Ms Samandeep Kour

Satellite orbital decay has emerged as a critical challenge in modern space operations owing to the proliferation of satellites, orbital debris, and extended-duration missions in Low Earth Orbit (LEO). This paper presents a comprehensive simulation-based analysis of satellite orbital decay and atmospheric re-entry under the combined influence of Earth’s gravitational perturbations and atmospheric drag. A Python-based numerical simulation framework was developed in Google Colab, integrating orbital mechanics, atmospheric density modeling, aerodynamic drag analysis, J2 perturbation effects, and Reaction Control System (RCS) based orbit correction techniques. Spacecraft motion was propagated via the Runge–Kutta RK45 adaptive integration method to ensure stable and accurate long-duration orbital prediction. The model evaluates key orbital parameters including altitude variation, orbital velocity, drag force, fuel consumption, and orbital lifetime under varying atmospheric conditions. Simulation results confirm that atmospheric drag is the dominant perturbation responsible for LEO orbital decay, causing gradual altitude reduction and eventual atmospheric re-entry. The implemented RCS system successfully executed orbital correction maneuvers compensating for altitude loss and enhancing mission stability. Validation of simulation outputs demonstrated strong agreement with established orbital mechanics theory and previously published research on atmospheric drag and orbital decay. Index Terms—Satellite Orbital Decay, Low Earth Orbit (LEO), Atmospheric Drag, Orbital Mechanics, Re-entry Prediction, Reaction Control System (RCS), J2 Perturbation, Numerical Simulation, RK45 Integration, Space Debris Mitigation, Orbital Lifetime Estimation, Python Simulation. "The simulation code is Uploaded available at https://colab.research.google.com/drive/10L5WWOOhJxlaOys2lGHMdEthu5mvAKKq?usp=sharing . ” Keywords: Simulation and Analysis of Satellite Orbital Decay and Atmospheric Re-Entry in Low Earth Orbit Using Python-Based Numerical Framework