Comprising an optical system, image sensor, processor, memory card, and housing – Star Tracker systems determine the precise location and attitude of a satellite or spacecraft by analysing the placement of the surrounding stars relative to the payload. Star Tracker optics are used to focus light from stars onto the image sensor.  The accuracy and reliability of a star tracker are highly dependent on the performance of the optical system. Poor optical design leads to blurred or distorted star images, which reduce the accuracy of attitude and bearing determination.