Recovery of the Wide-Field Infrared Explorer Spacecraft

The Wide Field Infrared Explorer was developed to perform astronomy using a cryogenically cooled infrared telescope. Shortly after launch, rapid venting of the cryogen, caused by an untimely cover removal, sent the spacecraft into an uncontrollable spin which exceeded 60 revolutions per minute. Over the next week, the WIRE team developed a plan and successfully executed the procedures necessary to de-spin the spacecraft and gain attitude control, but the cryogen for cooling the instrument was depleted. The recovery of the spacecraft enabled a thorough checkout of most of the subsystems, including the validation of several new technologies. Although the primary science mission was lost, WIRE is making breakthrough astroseismology measurements using its star tracker. This paper describes the recovery of the WIRE spacecraft and the performance of its key technologies, including the two-stage solidhydrogen cryostat, an all-bonded graphite-composite structure with K-1100 radiator panels, composite support struts, a dual-junction gallium arsenide solar array module, a concentrator solar array module, and a 300 Mbyte solid-state recorder