The radio galaxy B1610–605 within the Abell cluster A3627 has a low-brightness tail extending at least 26 arcmin from the nucleus of the 14 · 5m galaxy. The structure of this tail has been explored using observations with the Molonglo Observatory Synthesis Telescope (MOST) and the Australia Telescope Compact Array (ATCA). We present details of the brightness, width and alignment of the tail. The single tail expands and brightens rapidly within 2 arcmin of the nucleus. Confinement by the pressure of the cluster medium maintains a low but constant brightness for the tail between 10 and 25 arcmin. There are indications of turbulence down the tail but the position of the ridge remains within 1 · 6 arcmin of the initial alignment throughout its length.

High quality near-infrared (1-5 μm) spectra of SN 1987A have been obtained at MSSSO, AAO, ESO, CTIO and SAAO with good temporal coverage. These near-infrared observations are reviewed with particular reference to spectra obtained by the MSSSO group on the ANU 2.3m telescope at Siding Spring Observatory.

This paper suggests reasons why certain forms and frequencies are found in librations of the pole. The period is about 27 years, but there is also a shorter period which was found empirically to vary with the inverse of the amplitude of the Chandler nutation. It had been found also that the pattern of the motions would sometimes become reversed.

We have constructed theoretical spherical dust shell models using a full radiative transfer treatment, to investigate the effect of thermal emission on the strengths of molecular CO and H2O features in late type stars with circumstellar dust shells and to establish the optical depth at which the strengths of the bands are significantly affected. In this study, for the first time the central sources have been represented by realistic atmospheric models for cool stars in the temperature range 2500–3000 K, which are representative of the central stars of OH/IR sources. Parameters of the dust shell models were chosen to fit the observed run of colours from 1.25–5 μm of a large sample of OH/IR sources using ‘dirty silicate opacities’. The results show that the molecular band strengths in the 2 μm region are significantly affected by the dust emission only when the optical depth in the shell reaches a value of τ 1μm ≈2 for T* = 2500 K and somewhat less for T* = 3000 K. However, the changes are such that the distinction between supergiant-like spectra, and variable M-star spectra is retained in models with very high shell optical depths. The implications of these models are discussed in relation to previous observations of OH/IR sources.

A small radio astronomy group led by S.E. Williams in the Department of Physics at the University of Western Australia operated in the pioneering days. Observations were made of solar radiation at 75 Mc/s (4 m), using a polar-mounted Yagi antenna on the University campus in the Perth suburb of Nedlands. The group produced four papers, three in Nature and a longer one published locally. Although the work was noticed internationally, its influence on the course of radio astronomy seems to have been slight, and even the existence of the group has been almost forgotten outside of its home department.

The published properties of M1-78 are discussed with the purpose of resolving the object’s classification as either a planetary nebula or an ultracompact HII region. A classification as a planetary nebula is rejected primarily because of the high luminosity of the object, but because of the chemical composition and expansion velocity of the nebula, a novel classification is proposed instead: that of an ultracompact HII region with a post-main sequence central star (possibly a WN star). It must therefore follow that observable ultracompact HII regions persist beyond the main sequence lifetimes of at least some massive stars, and so cannot be transient phenomena that are seen only during pre-main sequence or early main sequence evolution.

The study of the sources of the slowly varying component at decimetre and centimetre wavelengths has been a major preoccupation of solar radio astronomers. Grating interferometers and other high-resolution aerial systems have enabled the separation of the S-component from the Sun’s total emission, and the study of individual sources. Nevertheless much of value remains to be derived from whole-sun intensity measurements—the most basic solar radio observation.

The properties of the M dwarfs have been investigated by spectroscopic and photometric observations of over 150 red, high proper motion stars. Most of these stars have red magnitudes fainter than 12 magnitude.

The alignment of galaxies within clusters and superclusters may be sought either in the major axis of the observed optical distribution or in any radio or X-ray structure from an active nucleus.

The most sensitive X-ray survey available is a deep exposure made by the Einstein Observatory of a 40 arcmin field in the southern constellation of Pavo. This survey revealed 33 X-ray sources, most of which were optically identified with quasars. Here, we report radio observations of the Pavo region at 843 MHz made with the Molonglo Observatory Synthesis Telescope. Eight overlapping fields were combined to produce the most sensitive radio map of the region to date, revealing 33 radio sources above a flux density of 2.4 mJy. Only one of these radio sources corresponded to an X-ray object: a quasar at z = 1.13. We also used the Parkes-Tidbinbilla Interferometer, at 2.29 GHz and 8.41 GHz, to observe some of the stronger radio sources.

From these multi-wavelength observations of the Pavo field it is apparent that, to the sensitivity of the surveys involved, (i) there is little correlation between X-ray and radio detections, and (ii) most of the X-ray sources have optical counterparts while few of the radio ones do, and (iii) there is some confirmation that X-ray emission is higher for objects with flat radio spectra (i.e., a dominant core) than for steep spectrum sources.

We report the development of a radio-linked interferometer which uses the 64-m telescope at Parkes, NSW, and one of the NASA antennas (64-m or 34-m) at Tidbinbilla, ACT. With a baseline of approximately 275 km, this is the world’s longest real-time interferometer; it will be usable at frequencies of 1.6, 2.3, 8.4, and 22 GHz to give angular resolutions of 0.13, 0.09, 0.03, and 0.01 arcsec respectively. The interferometer has already operated successfully in a limited mode and is expected to become fully operational in its initial configuration by September 1985. Operation at a range of frequencies and with progressive enhancements is planned up to the commissioning of the Australia Telescope in 1988.

In this review, I will be concentrating on problems related to the evolution of stars on the asymptotic giant branch (AGB). AGB stars are defined as stars which have completed core helium burning and have subsequently developed degenerate carbon/oxygen cores surrounded by hydrogen and helium burning shells; such stars have main sequence masses M≤9 M⊙ (Paczynski 1971; Becker and Iben 1980). In the HR diagram most AGB stars sit on the red giant branch. An exception to this rule occurs in Population II systems, where the AGB stars evolve asymptotically to the red giant branch from the blue side as the luminosity increases after completion of core helium burning on the horizontal branch.

we use Monte Carlo simulations of the period distribution of magnetic cataclysmic variables to show that the synchronised AM Herculis-type systems and the asynchronous Intermediate Polars are essentially unrelated systems following different evolutionary scenarios.

Observations of CO emission (Kutner et al. 1977) have delineated a molecular cloud extending over several square degrees in the Orion region, and extensive surveys have been made of several other molecules (e.g. CN, CS, HCN, H2CO, H2H+) in the densest regions of this cloud.

The baseline of East-West array of the Fleurs Synthesis Telescope (FST) has been extended from 786 metres to 1585 metres by the addition of two 13.7 metre dishes. A digital receiver has been built to accommodate the extra delay and correlation requirements, low noise FET preamplifiers have been installed on the large antennas, and a software package has been developed for processing observation data on a VAX 11/780. The FST is now capable of producing accurate wide field maps at 1415 MHz with a resolution of 20 arc seconds and a sensitivity of several milliJansky.