ROSAT FLIGHT EXPERIENCE WITH H/W-DEGRADATIONS AND S/W-RECOVERY MEASURES

ROSAT, launched on the 1st of June 1990, has opened a new era of X-ray astronomy. After about one year of operation, the attitude measurement system became faced with severe degradations of components. The paper describes how the fully autonomous mission could be reestablished by an onboard evaluation of magnetometer and coarse sun sensor measurements.