Review of the ProSEDS Electrodynamic Tether Mission Development

Abstract - The Propulsive Small Expendable Deployer System (ProSEDS) space experiment was ready to fly as a secondary payload on a Delta–II expendable launch vehicle in late March 2003. Concerns raised by the International Space Station (ISS) after the February 2003 Columbia shuttle accident resulted in the delay of the launch of ProSEDS. Issues associated with both the delayed launch date and a change in starting altitude resulted in the ultimate cancellation of the mission. ProSEDS was intended to deploy a tether (5-km bare wire plus 10-km non-conducting Dyneema) from a Delta–II second stage to achieve adequate electrodynamic drag thrust that would lower the orbit of the system over days—as opposed to months due to atmospheric drag. The experiment was also designed to utilize the tether-generated current to provide limited spacecraft power. Considerable effort and testing went into developing the ProSEDS system by a dedicated team. Throughout this effort, important technological issues were identified and addressed and this paper discusses some of the important technical issues and hurdles that had to be addressed to successfully prepare for flight. It is intended that this information will be of use for future tether mission and experiment designers.