Toshifumi Shimizu

The aim of sun sensors installed on spacecrafts is to measure the direction of the sun as precisely as possible, which signals are utilized to stabilize the spacecraft attitude. The Hinode (Solar-B) satellite has three telescopes for high spatial resolution observations of the sun and requires extremely stabilized pointing of the spacecraft. For achieving the pointing requirements, we have developed compact sun sensors named Ultra Fine Sun Sensor (UFSS), which are required to provide pointing signals with the random noise less than 1 arcsecond (3σ) and the bias noise less than 2 arcseconds (p-p) for the field-of-view with ± 0.5 degree. For verifying the performance with pre-launch measurements, we have established the methods of the measurements and have confirmed the excellent performance of the sensors.