Automatic removal of false image stars in disk-resolved images of the Cassini Imaging Science Subsystem  

作　　者：Qing-Feng Zhang Zhi-Cong Lu Xiao-Mei Zhou Yang Zheng Zhan Li Qing-Yu Peng Shun Long Wei-Heng Zhu 张庆丰;卢志聪;周晓妹;郑洋;李展;彭青玉;龙舜;朱蔚恒(Department of Computer Science,Jinan University,Guangzhou 510632,China;Sino-French Joint Laboratory for Astrometry,Dynamics and Space Science,Jinan University,Guangzhou 510632,China)

机构地区：[1]Department of Computer Science,Jinan University,Guangzhou 510632,China [2]Sino-French Joint Laboratory for Astrometry,Dynamics and Space Science,Jinan University,Guangzhou 510632,China

出　　处：《Research in Astronomy and Astrophysics》2020年第7期93-102,共10页天文和天体物理学研究（英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.11873026 and U1431227);the Natural Science Foundation of Guangdong Province,China(Grant No.2016A030313092);the National Key Research and Development Project of China(Grant No.2019YFC0120102);the Fundamental Research Funds for the Central Universities(Grant No.21619413)。

摘　　要：Taking a large number of images,the Cassini Imaging Science Subsystem(ISS)has been routinely used in astrometry.In ISS images,disk-resolved objects often lead to false detection of stars that disturb the camera pointing correction.The aim of this study was to develop an automated processing method to remove the false image stars in disk-resolved objects in ISS images.The method included the following steps:extracting edges,segmenting boundary arcs,fitting circles and excluding false image stars.The proposed method was tested using 200 ISS images.Preliminary experimental results show that it can remove the false image stars in more than 95%of ISS images with disk-resolved objects in a fully automatic manner,i.e.,outperforming the traditional circle detection based on Circular Hough Transform(CHT)by 17%.In addition,its speed is more than twice as fast as that of the CHT method.It is also more robust(no manual parameter tuning is needed)when compared with CHT.The proposed method was also applied to a set of ISS images of Rhea to eliminate the mismatch in pointing correction in automatic procedure.Experiment results showed that the precision of final astrometry results can be improve by roughly 2 times that of automatic procedure without the method.It proved that the proposed method is helpful in the astrometry of ISS images in a fully automatic manner.

关 键 词：methods:data analysis techniques:image processing techniques:telescopes stars:imaging 

分 类 号：P12[天文地球—天体测量]