<h2>AAS 99-194</h2>
<h2>On the Radial oscillation of an Electrodynamic Tether                                                                                            </h2>
<h4>J. Palaez*, M. Ruiz*, O. Lopez-Rebollal*, E.C. Lorenzini**                                                                                                                          </h4>
*ETSI Aeronatico, Madrid, **Harvard-Smithsonian Center for Astrophysics, Cambridge, MA                                                                                    
<h2> Abstract </h2>
The dynamic simulation of an electrodynamic tether shows a complex coupling between the radial motion of the end mass and the electrodynamic forces acting on the wire. A strong transfer of energy between the different degrees of freedom takes place in the radial motion and end mass. Neglecting the tether mass the conductive wire takes the form of an helix. Its axis along the Earth magnetic field. In out analysis a radial oscillation appears with a frequency higher than the orbital frequency and we show the characteristic equation of this oscillation.