Fig. 1
The distribution of radio sources in the ICRF1 (top panel) and ICRF2 (bottom panel) catalogs where the red open circles represent the 212 and 295 defining sources of corresponding catalogs, respectively. The arrows represent the proper motions of the defining sources resulting from the theoretical Galactic aberration. The catalogs are from the ICRS data center operated at Paris Observatory, http://hpiers.obspm.fr/icrs-pc/.
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