Japanese Balloon Telescope Program and Experiences

Pointing Control SystemGoal : To control telescope direction toward the target, and to pointing with0.1 arcsec accuracyThe three stage pointing control systemFirst : Gondola Attitude ControlAttitude of the gondola (Azimuth direction) is controlled to point the solar cellpanel toward the sun direction, and keep stable.Second : Coarse Pointing ControlAzimuth and elevation angle of the telescope are controlled to enter the targetin the filed of view and keep position of target on the center of the filed of view.Third : Fine Pointing ControlPosition of the target image is controlled with high accuracy during the exposureof the observation camera.