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The ROSAT spacecraft is a three-axes stabilized satellite which can be used for pointing at celestial targets, for slewing between such targets and for performing scanning observations on great circles perpendicular to the plane of the ecliptic. The two scientific experiments on ROSAT, the XRT and WFC, are coaligned; two star sensors are used for optical position sensing and attitude determination of the ROSAT spacecraft. The WFC carries its own star sensor for independent attitude determination; however, this sensor is not used for spacecraft control.
The spacecraft weighs about 2.4 tons, two thirds of which come from the scientific payloads. Power is supplied to the spacecraft through solar panels during the Sun-lit parts of the orbit; during nighttime (up to 40 minutes every orbit) through a rechargeable battery. Up to 700 Mbit of data can be stored on the two onboard tape recorders and transmitted to the ground during ground station contacts.