The proper motion and changing jet morphology of Cygnus X-3
  We present analysis of 25 years' worth of archival VLA, VLBA and EVN
observations of the X-ray binary Cygnus X-3. From this, we deduce the source
proper motion, allowing us to predict the location of the central binary system
at any given time. However, the line of sight is too scatter-broadened for us
to measure a parallactic distance to the source. The measured proper motion
allows us to constrain the three-dimensional space velocity of the system,
implying a minimum peculiar velocity of 9 km/s. Reinterpreting VLBI images from
the literature using accurate core positions shows the jet orientation to vary
with time, implying that the jets are oriented close to the line of sight and
are likely to be precessing.
