Abstract: In the process of space debris observation,interference with clouds is a bottleneck of optical telescope.This paper presented a new calculation method of the cloud amount,dividing the detected cloud image into twenty-four octants.The pixel values of each octant are counted,if the statistical results are greater than a given threshold T,it represents that the clouds of this octant are much more.If they are less than the threshold T,it indicates that there is no clouds covering in this octant,the telescope can be guided to the corresponding position of this octant.The research shows that this method is simple and easy to implement,it can realize the automatic guidance of the telescope and improve the observation efficiency.

Key words: Binaryzation, Cloud image segmentation, Cloud judgment, Telescope orientation