THE HIGH-TEMPERATURE SUPERCONDUCTIVITY SPACE EXPERIMENT - PRESENT STATUS AND FUTURE CHALLENGES

The High Temperature Superconductivity Space Experiment (HTSSE) at the Naval Research Laboratory (NRL) is exploring the feasibility of deplo ying high temperature superconducting (HTS) electronic devices, compon ents and subsystems in space. The initial HTSSE experiment, which empl oyed HTS technology available in 1990, focused on simple microwave dev ices which were suitably packaged, integrated with a cryogenic refrige rator and built into a space-qualified payload. Unfortunately the HTSS E-I payload, which was to have been launched in 1993, did not achieve orbit and was lost. The second HTSSE experiment, HTSSE-II, which emplo ys HTS technology circa 1993-94, consists of complex HTS components an d hybrid subsystems consisting of HTS and conventional semiconductor c omponents, the latter operating either at cryogenic temperature or at room temperature. The HTSSE-II payload containing the HTS components, cryogenic refrigerator and monitoring electronics was built, space qua lified and shipped from NRL to the satellite integrator in the Spring of 1996. The launch of HTSSE-II on the Advanced Global and Research Ob servation Satellite (ARGOS), which was originally set for mid-1996, is now scheduled for March 1998. A description of the HTSSE-II payload w ill be presented and the performance of the HTS components and their p otential impact on future space communications systems will be describ ed.