On determination of the Galactic aberration constant

Galactic aberration in proper motions (GA) has an amplitude (also known as the Galactic aberration constant) of about 5 µas/yr, which is substantial for the modern highly accurate astrometric observations such as Gaia and radio astrometry. There are several determination of the GA constant, but they don’t agree well. The estimates derived from radio astrometry (VLBI) and Gaia observations differ significantly, so it would be very desirable to involve another independent method to solve the problem of inconsistency between these two methods. In this paper, determination of the GA constant from the Galactic rotation parameters determined by methods of stellar astronomy is carried out. Obtained result showed that the GA constant estimate obtained from stellar astronomy agrees within errors with the estimate obtained from Gaia and does not agree well with the estimate based on VLBI observations of extragalactic radio sources.