标题： 长期色散漂移和甚长基线干涉测量未来挑战 显示英文标题

标题： The Secular Aberration Drift and Future Challenges for VLBI Astrometry

摘要： 太阳系由于银河系中心的引力吸引而产生的离心加速度，导致了一个被称为“长期光行差漂移”的现象。 到目前为止，在高精度天体测量的标准程序中，还没有考虑太阳系质心的这种加速度。 事实证明，当前定义的无历元和基于类星体没有可探测自行的假设的天体参考框架需要修订。 在未来，实现天体参考系统（无论是通过VLBI还是GAIA）应该修正这种效应导致的源坐标变化，可能通过提供源的位置及其自行来实现。 或者，银河系中心的加速度可以被纳入用于VLBI数据分析的传统群体延迟模型中。 显示英文摘要

摘要： The centrifugial acceleration of the Solar system, resulting from the gravitational attraction of the Galaxy centre, causes a phenomenon known as 'secular aberrration drift'. This acceleration of the Solar system barycentre has been ignored so far in the standard procedures for high-precision astrometry. It turns out that the current definition of the celestial reference frame as epochless and based on the assumption that quasars have no detectable proper motions, needs to be revised. In the future, a realization of the celestial reference system (realized either with VLBI, or GAIA) should correct source coordinates from this effect, possibly by providing source positions together with their proper motions. Alternatively, the galactocentric acceleration may be incorporated into the conventional group delay model applied for VLBI data analysis.