A UNIVERSAL SYSTEM TO DE-ORBIT SATELLITES AT END OF LIFE Juan R. SANMARTIN, Mario CHARRO, Xin CHEN Universidad Politecnica de Madrid, Madrid, Spain Enrico C. LORENZINI, Giacomo COLOMBATTI, Denis ZANUTTO Universita degli Studi di Padova, Padova, Italy Jean-Francois ROUSSEL, Pierre SARRAILH ONERA, Toulouse, France John D. WILLIAMS, Kan XIE, Garrett E. METZ Colorado State University, Fort Collins, CO, United States Jose A. CARRASCO, Francisco GARCIA-DE-QUIROS Embedded Instruments and Systems S.L., Elche, Spain OlafKROEMER, Roland ROSTA, Tim van ZOEST DLR German Aerospace Center, Bremen, Germany Joseba LASA, Jesus MARCOS Fundacion Tecnalia, San Sebastian, Spain juanr. sanmartin@upm. es Abstract A 3-year Project financed by the European Commission is aimed at developing a universal system to de-orbit satellites at their end of life, as a fundamental contribution to limit the increase of debris in the Space environment. The operational system involves a conductive tape- tether left bare to establish anodic contact with the ambient plasma as a giant Langmuir probe. The Project will size the three disparate dimensions of a tape for a selected de-orbit mission and determine scaling laws to allow system design for a general mission. Starting at the second year, mission selection is carried out while developing numerical codes to implement control laws on tether dynamics in/off the orbital plane; performing numerical simulations and plasma chamber measurements on tether-plasma interaction; and completing design of subsystems: electron- ejecting plasma contactor, power module, interface elements, deployment mechanism, and tether-tape/end-mass. This will be followed by subsystems manufacturing and by current- collection, free-fall, and hypervelocity impact tests. 1. Introduction BETs (Propellantless deorbiting of space debris by bare electrodynamic tethers) is a 3-year Project started on November 1, 2010, financed by the European Commission within the FP-7 Space Program, and aimed at developing an efficient de-orbit system that could be carried on board any future satellite launched into Low Earth Orbit. A dedicated system is needed because satellites naturally orbit at ionospheric altitudes where air drag is very weak. The operational system will deploy a conductive thin-tape bare-tether to collect electrons as a giant Langmuir probe, using no propellant and no power supply, and generating power on board.