Trajectory Approximation of a Coulomb Drag-Based Deorbiting

The presence of a number of space debris in low Earth orbits poses a serious threat for current spacecraft operations and future space missions. To mitigate this critical problem, international guidelines suggest that an artificial satellite should decay (or be transferred to a graveyard orbit) within a time interval of 25 years after the end of its operative life. To that end, in recent years deorbiting technologies are acquiring an increasing importance both in terms of academic research and industrial efforts. In this context, the plasma brake concept may represent a promising and fascinating innovation. The plasma brake is a propellantless device, whose working principle consists of generating an electrostatic Coulomb drag between the planet's ionosphere ions and a charged tether deployed from a satellite in a low Earth orbit. This paper discusses an analytical method to approximate the deorbiting trajectory of a small satellite equipped with a plasma brake device. In particular, the proposed approach allows the deorbiting time to be estimated through an analytical equation as a function of the design characteristics of the plasma brake and of the satellite initial orbital elements.