A Geometric Distortion Solution Specifically for Historical Observations and its Implementation  

作　　者：F.R.Lin Q.Y.Peng Z.J.Zheng B.F.Guo 

机构地区：[1]School of Software,Jiangxi Normal University,Nanchang 330022,China [2]Sino-French Joint Laboratory for Astrometry,Dynamics and Space Science,Jinan University,Guangzhou 510632,China [3]Department of Computer Science,Jinan University,Guangzhou 510632,China [4]Guangdong Ocean University,Zhanjiang 524000,China

出　　处：《Research in Astronomy and Astrophysics》2024年第11期85-94,共10页天文和天体物理学研究（英文版）

基　　金：supported by the National Key R&D Program of China(grant No.2022YFE0116800);the National Natural Science Foundation of China(NSFC,grant No.12203019);the Natural Science Foundation of Jiangxi Province(grant No.20242BAB20033);the NSFC(grant Nos.11873026 and11273014);the China Manned Space Project(grant No.CMS-CSST-2021-B08);the Joint Research Fund in Astronomy(grant No.U1431227)。

摘　　要：Geometric distortion(GD)critically constrains the precision of astrometry.Using well-established methods to correct GD requires calibration observations,which can only be obtained using a special dithering strategy during the observation period.Unfortunately,this special observation mode is not often used,especially for historical observations before those GD correction methods were presented.As a result,some telescopes have no GD calibration observations for a long period,making it impossible to accurately determine the GD effect.This limits the value of the telescope observations in certain astrometric scenarios,such as using historical observations of moving targets in the solar system to improve their orbits.We investigated a method for handling GD that does not rely on the calibration observations.With this advantage,it can be used to solve the GD models of telescopes which were intractable in the past.The method was implemented in Python and released on GitHub.It was then applied to solve GD in the observations taken with the 1 m and 2.4 m telescopes at Yunnan Observatory.The resulting GD models were compared with those obtained using well-established methods to demonstrate the accuracy.Furthermore,the method was applied in the reduction of observations for two targets,the moon of Jupiter(Himalia)and binary GSC 2038-0293,to show its effectiveness.After GD correction,the astrometric results for both targets show improvements.Notably,the mean residual between the observed and computed position(O-C)for binary GSC 2038-0293 decreased from 36 to 5 mas.

关 键 词：astrometry-methods data analysis-techniques image processing 

分 类 号：P111[天文地球—天文学]