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We present world-array VLBI observations of the blazar 1803+784 performed on May 29, 1993 at λ = 18 cm. A 17-station VLBI array, the phased VLA and the 7-station MERLIN array observed the source simultaneously for 11 h. We present the global VLBI map, the MERLIN map, and combined-array maps at different resolutions giving an overview of the morphology of 1803+784 from the inner 10 mas to ∼2 arcsec. We show that the jet bends by around 90• at a core separation of about 0.5 arcsec towards the South. On larger scales, a Westerbork Synthesis Radio Telescope (WSRT) map made at a wavelength of 6 cm resolves the bridge connecting the core with the secondary component some 45 to the south. Wiggles in the ridge of this emission suggest that, as on the 100-pc scale, the jet may also oscillate on 50−100 kpc scales. In addition to improved imaging of the southern component, the 6 cm map provides evidence for amorphous emission to the north, as well as an extended, halo-like component about the nucleus. We compare the source structure at 6 and 18 cm with the structure at 2 cm in a VLBA image obtained on November 6, 1999. Jet wiggling is clearly seen on all scales between 1 mas and 50 arcsec. We find some indication for apparent superluminal motion between ∼5c and 7c for the 25 mas jet component in model-fit results for five epochs of VLBI observations performed at 6 and 18 cm. In addition, we find some evidence for further so-called stationary components in the jet of this source which will have to be confirmed in future observations spaced more densely in time. We discuss the self-similar source morphology observed from mm to cm wavelengths -namely the wiggling on all observed scales -and the implications of the deviations from self-similarity. This is the second of two papers describing the radio structure of S5 1803+784. The first presented the results of 6 years of VLBI monitoring in the X-band (Britzen et al. 2005, MNRAS, in press).

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A global array of 20 radio observatories was used to measure the three-dimensional position and velocity of the two meteorological balloons that were injected into the equatorial region of the Venus atmosphere near Venus midnight by the VEGA spacecraft on 11 and 15 June 1985. Initial analysis of only radial velocities indicates that each balloon was blown westward about 11,500 kilometers (8,000 kilometers on the night side) by zonal winds with a mean speed of about 70 meters per second. Excursions of the data from a model of constant zonal velocity were generally less than 3 meters per second; however, a much larger variation was evident near the end of the flight of the second balloon. Consistent systematic trends in the residuals for both balloons indicate the possibility of a solar-fixed atmospheric feature. Rapid variations in balloon velocity were often detected within a single transmission (330 seconds); however, they may represent not only atmospheric motions but also self-induced aerodynamic motions of the balloon.