IADC AI 19.1 on 'Potential Benefits and Risks of Using Tethers for End-of-life De-orbit of LEO Spacecraft'. Final Results and Draft Report

Despite a small number of full-scale experiments made so far using space tethers, the possibility of de-orbiting spacecraft by means of electrodynamic tethers has been on the drawing board of theorists for almost a decade. By using electrodynamic drag to greatly increase the orbital decay rate, an electrodynamic space tether can remove spent or dysfunctional spacecraft from low Earth orbit rapidly and safely. However, a tether system is much more vulnerable to space debris impacts than a typical spacecraft and its design must prove to be safe to a certain confidence level before being adopted for potential applications. To assess the space debris related concerns, a task on the benefits and risks of using electrodynamic tethers to de-orbit spacecraft was defined by the Inter-Agency Space Debris Coordination Committee (IADC), in March 2001. The task was assigned to the IADC Working Group 2, on 'Environment and Data Base', and a study plan was formulated with the main objective of investigating the potential risk to the tether system integrity due to impacts with space debris. IADC members of three agencies (ASI, JAXA and NASA) participated in the study and different computational approaches were specifically developed in the framework of this IADC task. This presentation introduces the potential benefits and risks of using tethers to de-orbit satellites, presents the assumptions made in the study plan,compares and discusses the results obtained by ASI, JAXA and NASA for the tests proposed.