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We present new optical observations of the nearby barred spiral galaxy Dwingeloo 1 (Dwl) obtained with the Isaac Newton, William Herschel and Wise telescopes. Dwl lies at Galactic coordinates (I = 138 ~ 52, b =-0 ~ 11) and it is heavily obscured by dust and gas in the Milky Way. We infer that Dwl is of morphological type SBb or SBc (T = 4), has an inclination i ~ 50°, a position angle PA ~ 110°, and a recession velocity relative to the Milky Way V Mw =256 ± 9 km S-1. The measured total apparent magnitudes of Dwl are V=14.0±0.5, R=12.2±0.2 and 1= 10.7 ±0.2. The extinction estimate towards Dwl is highly uncertain. The extinction in the B band, derived from Galactic H I column density measurements, is AB ~ 5.8. Estimated from Galactic 100-llm emission, the extinction is AB~4.3, while the reddened colours of Dwl yield an estimate of AB ~ 10.4. Assuming AB = 5.8, Tully-Fisher relations in the I and R bands lead to a distance estimate for Dwl of D ~ 300 km S-1. However, for the derived range of extinction estimates 4.3;;;:;AB;S1O.4, the distance varies from 100 to 500 km s-1. We also report the detection of numerous H II regions associated with Dwl, and present data from the Infrared Astronomical Satellite (IRAS) archive.

In regions away from the Galactic plane, formal tests indicate an isotropic, random and independent distribution of radio sources on the sky (e.g.[1], although there are strong indications of large-scale anomalies (e.g.[2], [3]). An accommodation of these results was suggested by Shaver and Pierre [4] and by Shaver [5] who showed that the large-scale deviations could be due to the supergalaxy, a possibility which had been noted by Pauliny-Tothet al.in 1978 [6]. As to the influence ofothersuperclusters, or indeed the cellular structure of the universe in which galaxies cluster on scales up to at least 100h−1Mpc (e.g.[7]), at what flux-density level does this large-scale structure become apparent? Conversely, what can be learnt about structure on the largest scales through the sky distribution of radio sources? Here we describe three investigations in various stages of completion which consider these issues.