Abstract: CCD noise is an error source of guide star position of star sensor. The DV437-BU2 CCD chip’s dark current, dark current shot noise and dark current non-uniform noise characteristics of temperature have been measured in this paper. The effect of CCD chip’s temperature on star position accuracy has been researched. The results show that decreasing CCD chip’s temperature could improve the star position accuracy effectively when the temperature is higher than 300K, but could not remarkably when the temperature is lower than 300K. The star position accuracy level is improved from 0.12 pixel to 0.078 pixel when the temperature reduces from 330K to 300K.

Key words: CCD')">CCD, noise, star sensor, position accuracy, ')">refrigeration