IERS天球参考架的指向维持

THE MAINTENANCE OF THE ORIENTATION OF IERS CELESTIAL REFERENCE FRAMES

本文分析了河外射电源坐标系不统一问题对ＩＲＲＳ天球参考架指向维持的影响。由于１９８８年至１９９１年各年度的ＩＥＲＳ河外射电源综合表中基本源与非基本源坐标系不统一的程度各不相同，所以不能在每年的指向上加入相同的改正量，本文在重新归算１９８８年至１９９１年历年综合表的基础上，给出了历年ＩＥＲＳ综合河外射电源表的指向改正，并建议对１９９３年的综合表进行相应的指向调整。

The effects of the problem of inconsistent coordinates in the IERS combined catalogues from 1988 to 1991 on the maintenace of the orientation of IERS celestial reference frames are discussed.It is pointed out that remedies adopted by IERS are only advisable to prevent the occurrence of similar problems in the following versions of IERS radio source catalogues.But these are insufficient to eliminate the effects which had been resulted from this problem.Since the extent of the incosistence in coordinates is different for different catalogues,combined catalogues for years from 1988 to 1991 must be reconstructed and the orientation of the catalogues of 1992 and 1993 must be re-adjusted accordingly.In order to maintain the initial orientation of the IERS celestial reference frame which was defined in 1988,the angles must be applied to the catalogue of 1992 are as follows(unit:1 mas):A1 =-0.01±-0.05,A2=0.54±-0.05,A3=-0.29±0.04.