The star-formation process is an outstanding and largely unsolved problem in astrophysics. The role of magnetic fields is unclear but is widely considered to be important at all stages of protostellar evolution, from cloud collapse to ZAMS. For example, in some hydromagnetic models, the field may assist in removing angular momentum, thereby driving accretion and perhaps bipolar outflows.

Spectropolarimetry between 8 and 13μm provides information on the direction of the transverse component of a magnetic field through the alignment of dust grains. We present results of 8–13μm spectropolarimetric observations of a number of bipolar molecular outflow sources, and compare the field directions observed with the axes of the outflows and putative disk-like structures observed to be associated with some of the objects. There is a strong correlation, though so far with limited statistics, between the magnetic field and disk orientations. We compare our results with magnetic field configurations predicted by current models for hydromagnetically driven winds from the disks around Young Stellar Objects (YSOs). Our results appear to argue against the Pudritz and Norman model and instead seem to support the Uchida and Shibata model.

Several methods are available for sensitizing photographic plates, each with its own disadvantage. Pre-flashing greatly increases the plate background and is useful only for enhancing the plate’s response to light levels near the plate’s threshold. Baking and (or) evacuating enhance the plate’s response at all light levels and leave a slightly higher background. Unfortunately all of these methods produce plates with a short shelf life after sensitization.

The authors discuss the light-pollution prevention ordinance passed by the Japanese town of Bisei in 1989.

There are many thousands of photographic star plates in observatories throughout the world, and the number is being added to continually. A major difficulty in making use of the information contained in them lies in the measurement of position, and other data, of star images on the plates, and in bringing the data to a form suitable for computer processing. Manual methods are impossibly slow and laborious for an extended program of measurements, and automatic machines on the market are prohibitively expensive for small observatories with limited resources.

The U-burst, first identified by Maxwell and Swarup and Haddock, is a type of solar radio event lasting ~ 10 s in which the frequency of the emission at first drifts rapidly downwards, then increases again. On the dynamic spectrum record the burst has the appearance of an inverted letter U.

We have designed and manufactured a multi-purpose electronic, computer-operated blink-comparator and measuring engine. It has been specifically designed to facilitate the examination of stellar images on Uppsala Schmidt photographic plates, identify and establish coordinates of new suspect variable stars appearing on the plates being examined, and also to derive photometric values for those stars manifesting variability.

It can be shown that cepheids pulsating in the first harmonic when evolving through the instability zone at constant bolometric luminosity and mass, are at a given period 0.09 magnitudes bluer than stars pulsating in the fundamental mode. Bell and Rodgers have shown that effective temperatures of cepheids can be obtained by comparison of observed and computed profiles of the wings of the Hα line. Hα cores of cepheids are affected by strongly doppler broadened chromospheric emission and absorption. Using a modified Oke effective temperature-intrinsic colour relation, observations of the Hα line of the Eggen C cepheids β Dor and S Mus have been made at Mt. Stromlo and intrinsic colours obtained for these stars.

The 1.04 m telescope and auxiliary instrumentation conceived some ten years ago, are now operational and starting to produce results. Whilst the original purpose of the telescope was high dispersion spectroscopy alone at Coudé focus, access to a folded Cassegrain focus has been added to enable photometric observations to be made.

Global magnetic structure has been inferred in spiral galaxies from radio and optical observations. The author has developed a three dimensional, quasi-global kinematic dynamo model which demonstrates the possibility of maintaining large-scale magnetic fields by the αω mechanism. Analytical expressions for large-scale galactic magnetic fields near temporal steady states have been derived. Illustrations of the spatial distribution of vector and absolute large-scale magnetic field strength are presented. When coupled with observations this model may help in understanding the maintenance and morphologies inferred for disk and halo global magnetic fields in spiral galaxies.

In the field of cosmic ray galactic studies, two kinds of phenomenon are currently being investigated by members of the Hobart cosmic ray group, led by Dr. A. G. Fenton. In a combined project with the University of South Australia, the University of Tasmania is participating in an experiment whose aim is to locate sources of galactic X-rays in a part of the southern sky inaccessible from the northern hemisphere. The object of the other investigation, which forms part of a joint ANARE-University programme of cosmic ray research, is to elucidate the evidence for intensity maxima from fixed galactic directions in the otherwise isotropic charged primary radiation.

This paper presents a measurement of the diffuse cosmic X-ray background made during the balloon flight described in preceding papers and elsewhere. The data used for this paper were obtained with the actively shielded and collimated detector previously described. The geometric factor of the detector was 1.17 cm2 sterad.

The wavefront from a celestial source is believed to arrive at the outer fringe of the Earth’s atmosphere as a truly plane wave of effectively infinite extent. After propagating through our refractively non-uniform atmosphere this wavefront becomes distorted in shape and exhibits a nonuniform amplitude distribution. At present there is little that can be done to remedy the effects of the atmosphere on wave propagation. However when the wave has been received by the entrance aperture of the observing telescope we should try to design this optical system, including its air-path sections, so as to minimize further distortion of the wavefront. ‘Seeing’ effects within an instrument which concern us in this paper are attributable to air of nonuniform temperature (and hence refractive index) in the sections between the optical components.

A time scale may be defined as a system for dating events. A clock is a device for interpolating between observations of the time scale. From antiquity, time scales have been based on the earth’s rotation; even today, the atomic-based time scale Universal Coordinated Time (UTC) is adjusted annually, or when necessary, to keep it in time with the rotating earth. However, the continual search for greater accuracy in time keeping has led to the adoption of time scales based on other phenomena, so that there are now four classes of time scales in use, as summarised in Table I.

We have secured spectra at high signal/noise ratio in a grid of points across the entire Homunculus Nebula surrounding the peculiar, massive star η Carinae. The data cover the wavelength range 420–1000 nm. Included are parts of the outer nebulosity dating from a prehistoric ejection episode. At a spatial resolution of about 1 arcsec we find dramatic differences in emission Ime ratios and profiles, sometimes in adjacent resolution elements.

In April of this year agreement was reached between the British and the Australian Governments to build a 150-inch telescope for observations of the southern sky.

The agreement specified that:

• (i) the telescope would be built at the Australian National University’s present site at Siding Spring Observatory;

• (ii) the expected cost was $11 million and the telescope would be built and operated on a 50-50 basis as between the two Governments;

• (iii) the telescope would be virtually a copy of the existing Kitt Peak 150-inch design. This was intended to save the time usually needed for the design of a new telescope and, as we shall see, it might lead to considerable savings in cost.