Published online by Cambridge University Press: 03 August 2017
The effect of the superluminal motion of 3C273b was observed on the fringe amplitudes obtained in VLBI experiments which have been conducted on the baselines between Japan and United States since 1984 under the Crustal Dynamics Project. The speed was 0.7 mas/year and the direction was −83 degrees in the position angle. It was also confirmed as the apparent right ascention shift of the source.