The Effect of Galactic Aberration on the CRF

Abstract

International audienceWe compare two Celestial Reference Frame (CRF) solutions made from Very Long Baseline Interferometry (VLBI) group delay observations in S/X band using vector spherical harmonics. In both solutions the same data set was used which consists of almost all observations since 1979 until the beginning of 2018. The same parameterization and models were used with the exception that in one of the solutions the effect of galactic aberration (GA) was corrected. The other solution serves as a reference. We show that the deformation of a CRF estimated with the whole set of VLBI observations can be described by a systematic dipole displacement with an amplitude of about 35 ?as