Modeling Orbital Decay of Low-Earth Orbit Satellites due to Atmospheric Drag: A Simplified Analytical Approach

Low-Earth Orbit (LEO) satellites are crucial for communications, navigation, and Earth observation. However, their operational lifetimes are strongly influenced by orbital decay due to atmospheric drag. This work presents a simplified analytical model of orbital decay in LEO, incorporating atmospheric density variations and satellite parameters. Using standard drag force equations and density models, we explore how altitude, satellite mass, and cross-sectional area affect decay timescales. Comparisons are made with existing NASA models and previous literature. The results highlight the importance of accurate atmospheric density representation and solar activity in predicting satellite lifetimes, especially relevant in the context of increasing space debris and mega-constellations.