Work on the development and use of optical fibres as light guides in astronomical spectroscopy has been underway at the AAO for over a year now. The fibres used are step-index polymer-clad silica with a core size of 200 microns giving an aperture size of 1.3 arcsec at the AAT f/8 focus. They are optimised for data transmission with losses below 5dB/km at a wavelength of 800 nm. The blue transmission is somewhat lower, typically 500dB/km at 300nm and 90dB/km at 400nm but over the short 2m length used these attenuations give transmissions of 79% and 96% respectively.

8.4 GHz linear polarization maps, obtained with the Parkes radio telescope, are presented for six southern supernova remnants. These results are compared with published and unpublished polarization maps at 5 GHz to derive the magnetic field direction and Faraday rotation measure distribution.

These results are part of a program to map the magnetic fields in galactic supernova remnants and complement our program to obtain high-resolution maps of galactic SNRs using the Molonglo Observatory Synthesis Telescope; five new Molonglo maps are presented here.

The interpretation of the radio burst from SN 1987A as an expanding synchrotron source is briefly reviewed.

This paper describes some of the space science programs currently underway and planned in Japan.

The mechanism by which planetary nebula (PN) shells are ejected is still subject to considerable uncertainty. It is generally assumed that the precursors of these objects are low mass (M< 5 M⊙) asymptotic giant branch (AGB) stars, and that the nucleus of a planetary nebula (NPN) is undergoing a final gravitational contraction to the white dwarf state. The shell consists of some or all of the remaining unburnt (though not necessarily uncontaminated), hydrogen-rich material out of which the star was originally formed.

The double-mode or beat Cepheids continue to pose a number of interesting questions in our search for an understanding of the pulsation properties of stars near the short period end of the instability strip. One such is how simultaneous pulsations in the fundamental and first overtone radial modes can occur for an appreciable fraction of Cepheids in the period range 1d < Pо < 5d.

Charles Todd was the first Government Astronomer and Superintendent of Telegraphs in South Australia. Most widely known for his instrumental role in the construction of the Overland Telegraph, linking Australia and England, Todd also established the Adelaide Observatory and made valuable contributions to both astronomy and meteorology.

Recently (Gleeson (1972), Quenby (1973), Gleeson and Webb (1974, 1978)) it has been shown that the mean rate of change of momentum of cosmic rays reckoned for a volume fixed in the solar system is

where G = (1/Up )(∂Up /∂r)si the cosmic-ray density gradient with Up , the differential number density with respect to momentum p at position r. (cf also the integral form of (1) by Jokipii and Parker 1967).

Operation of the six 13.7 m antennas of the Fleurs synthesis telescope as a sub-array has provided a new and surprisingly versatile astronomical tool. With enhanced reliability and fully automated operation, unattended observing over several days is possible. Interleaved ‘multiple-snapshot’ observations of many fields per day can be made.

The array has shown itself to be particularly suitable for the measurement of precision (a few arcsecond) positions for the optical identification of a large number of radio sources, a survey of compact sources and the monitoring of the activity of several radio stars over periods of weeks. At present a program of recalibration is under way to improve the positional accuracy and dynamic range of the instrument.

Surface photometry of the elliptical galaxy NGC 1700 is presented and discussed in terms of providing evidence for warping of the outer isophotes in elliptical galaxies.

We shall examine the question of whether the concentration of magnetic field, the downward motion and the temperature excess observed at the boundaries of supergranules can be interpreted consistently in terms of a steady flow along the magnetic lines of force. Before doing so, however, we shall first consider the development of the magnetic configuration driven by a supergranular convection overshooting into the photosphere.

Spectroscopic imaging of the SNR RCW 103 has revealed extensive emission in near-infrared lines of H2and [Fe II], where the blast wave is encountering a molecular cloud. The H2 appears to be located outside the [FeII], a morphology which challenges our understanding of shock wave physics. It is suggested that reverse shocks may be responsible for the phenomenom.

We present observational results obtained during the first three years following the explosion of Supernova 1987 A. We discuss aspects of the optical and near infrared spectra as well as results from spectropolarimetric observations. The observations of the circumstellar and interstellar medium are also briefly discussed.

The absolute measurements of flux emitted in the visible continua of some Galactic Wolf-Rayet stars were carried out by means of a two-channel scanner. The measurements lead to the determination of stellar angular diameters which enable us to compute log L */L ⊙. The stellar wind terminal velocity, V ∞ was obtained from the empirical relation of the effective temperatures by Underbill (1983) and V ∞, adopted from the work of Willis (1982). Also, we derived the rate of mass loss for the WR stars from the formula Ṁ = є(T eff)L/(V ∞ c) by using the obtained effective temperatures, luminosity and V ∞ in this work. The values of the rates range from 1.4 × 10−5 to 5.8 × 10−5M ⊙yr−1.

The lack of any direct measurements on the spin temperature of the neutral hydrogen in the Galaxy has led to considerable controversy in the past. Estimates of the temperature have depended strongly on whether they are based on emission or absorption studies. The widely accepted value of 125°K based on emission studies dates back to Schmidt. He adopted this figure on the premise that the maximum observed brightness temperatures in the galactic plane were in directions of high optical depth. The brightness temperature was then equated with the spin temperature on the assumption that the temperature did not fluctuate very much in a large region around the Sun.

The discovery of the variability of the eclipsing system UX Eri can be attributed to Soloviev (1937). Photographic observations were made by Zessewitsch (1934, 1954), Bodokia (1938) and Gaposchkin (1953). Photoelectric observations were obtained by Kitamura and Nakamura (1957). The most recent photoelectric data were obtained by Binnendijk (1967) who determined new orbital elements. During the 10-year period from 1967-1977 the variable appears to have received little attention.

Advances in digital computer technology since the middle decades of the twentieth century have transformed many subject areas in astrophysics. Topics which had previously been dealt with by analytic approximations (usually to a very limited number of special cases) suddenly became amenable to detailed numerical modelling for all cases. Frequently, insights derived from this modelling ran ahead of other techniques in predicting physical phenomena before they were either observed or discerned in purely analytic treatments.

It has sometimes been said that the second half of this century has seen the advent of a totally new modus operandi in scientific research, which ranks alongside the two traditional approaches–experimentation and theory. The most powerful computers now available have greatly accelerated these developments. They employ simultaneous computational techniques (either vector processing or parallel processing, or both), and their throughput is so large that, for most problems, the only way in which the human mind can fully appreciate the scientific content of the numerical results being calculated is by transforming those results into pictorial representations.

This paper draws on my experience as Academic Director of the ANU Supercomputer Facility during the first eighteen months of its operation, to describe the place which I believe super-computers will occupy in the development of astrophysics during the 1990s and into the next century.

The primary objective of the LYMAN Mission is to provide an Observatory for the study of the waveband between 900 and 1250Å. Only one previous mission, Copernicus, has given us a glimpse into the very rich astrophysical return offered in this far-ultraviolet part of the electromagnetic spectrum. However, LYMAN will provide a sensitivity some ten thousand times greater than Copernicus.

It is the enormous richness of this part of the electromagnetic spectrum which is the prime justification of the mission. No other region offers such a density and variety of atomic, ionic and molecular absorption lines. Collectively, these represent a tool of great diagnostic power in determining physical conditions and chemical compositions of astrophysical plasmas. These plasmas may be cool, and seen in absorption against a hot continuum source, or else they may be hot and emitting in their own right. In either case, LYMAN is the ideal vehicle for their study, be they in solar system objects, near newly-forming stars, in photospheres, transition layers, or coronae of stars, in interstellar or intergalactic space, or close to the active cores of galaxies. For this reason, LYMAN will be a uniquely powerful tool for use in all branches of modern day astrophysics.