HD 44179, a ninth-magnitude star of late B spectral type, is peculiar in several respects. At red wavelengths it appears to be located at the apex of a biconical nebular (‘The Red Rectangle’) of dimensions about 1′ arc. Cohen et al. (1975) identified the system with the bright infrared source AFGL 915 and carried out investigations at optical, infrared and radio wavelengths. The complexities of the spectra have continued to interest astronomers.

Recent numerical experiments (Norman et al. 1980), which simulate the axisymmetric collapse of a rotating, self gravitating cloud, show that spurious angular momentum transport can seriously affect the evolution of the cloud. In particular, it may determine if a ring-like density enhancement will occur. The spurious angular momentum transport can arise either from an explicit artificial viscosity, which might be required if shocks occur, or from an implicit viscosity due to truncation errors in the difference equation approximation to the exact equations. In donor cell schemes like those used by Tohline (1980) and Boss (1980) spurious angular momentum transport is due to truncation errors in the difference equations. For axisymmetric problems the errors are usually not serious since the typical length of a cell in the computational grid is very much less than the length scale of the cloud. We would expect the errors to be much greater when fragmentation occurs because the length scale of a fragment may only be comparable to that of three or four cells.

The Parkes 64 m telescope has been used to survey a complete sample of nearby red giants (i.e. not members of close binaries or showing strong emission lines of CaII). The sample consisted of all 82 stars in the Bright Star Catalogue within 30 pc having spectral types G, K, M and luminosity classes I, II, III south of the celestial equator.

Print copies of the Palomar Sky Survey (PSS) are widely used for optical identifications of radio sources north of δ = -33°.

Extensive observations of the spectra of the decametric radio bursts for Jupiter have been made by Riihimaa, principally at frequencies between 18 and 23 MHz and with frequency resolution of 50 kHz. These showed much fine frequency-time structure in the bursts but pointed to the need for higher frequency resolution and greater antenna sensitivity. This paper reports the results of observations made of the Jupiter bursts between February and April, 1972, using the Llanherne low frequency telescope (Ellis,).

While Centaurus A (NGC 5128) is not a particularly powerful radio galaxy, its proximity (˜ 5 Mpc) permits us to obtain linear resolution an order of magnitude better than can be obtained for the more powerful, distant radio galaxies. Thus one can hope to make meaningful comparisons between the morphologies seen over the electromagnetic spectrum from γ-rays to metre waves. This should lead to a more complete understanding of the energy production mechanisms and evolutionary histories of these objects.

The Sydney University one mile cross-type radio telescope at the Molonglo Radio Observatory has been used to study the 30 Doradus nebula with high resolution (~3´ arc) at 408 MHz. This preliminary report compares these observations with Balmer line isophotes published by Faulkner. A description of the calibration procedures used in the present observations, an analysis of the various radio features in the 30 Doradus region, and a comparison with previous observations at other frequencies, will be described in a later paper.

An apparent connection is reported between the magnetic field strengths inside an electron, in newly born pulsars, and the sun. It is argued that the upper limit to the strength of magnetic field which seems to exist is that which would permit emission of a photon at the non-relativistic electron gyrofrequency, with energy of the order of the electron rest mass. The strongest magnetic fields at the surface of polar regions of pulsars conform to this. By equating approximately the rest mass of an electron to its magnetic energy, the same magnetic field is found inside the electron. It is proposed that magnetic field building ‘blocks’ called M-particles are formed by a variant of the electron-positron spin-zero annihilation. The particles become as tightly stacked as possible to form the macroscopic magnetic field of the newly born pulsar. The sun’s present magnetic moment is described by a pulsar-sized object at its centre, with the maximum packing of M-particles. The hypothesis may have a bearing on the formation of magnetic fields in celestial bodies, and on the secular variation of the magnetic fields of the sun and the Earth.

Proxima Centauri was observed photoelectrically in the period July-September 1987 with a newly-installed computer-interfaced photometer. Four definite flares and six further possible events were recorded. The level of Proxima’s flaring activity was examined and no significant change since 1969 found.

High-resolution radio maps of supernova remnants (SNRs) are indispensable for distinguishing the more common shell remnants from the centrally concentrated (Crab-like) remnants; such studies also reveal any departures from symmetry, and this can yield vital information concerning interaction of the ejecta with the surrounding interstellar medium.

Data from the Solar Maximum Mission satellite suggests that there is a 0.1 percent variation in solar luminosity over the 11-year solar cycle with maximum output corresponding to maximum sunspot number. Tree ring chronologies can be utilized as proxy data to compile a record of the magnitude of past solar variability. Spectral analysis of tree ring series compiled from a site in Tasmania has established, among others, significant periodicities of about 90 and 11 years. The application of band pass filter techniques shows that the 11-year cycle present in some tree ring series correlates with the Zurich sunspot numbers over the period from AD1700, the extent of accurate sunspot records, with a time lag of about three years.

Radio contours are presented for Fornax A (NGC 1316), Virgo A (NGC 4486) and the central component of Centaurus A (NGC 5128). These three objects are intrinsically strong radio emitters identified with bright galaxies. The work forms part of a survey of all bright galaxies with the Molonglo cross down to a corrected total magnitude of 11m.0 with an extension down to photographic magnitude 12m.5 in an limited region of the sky.

Simultaneous high dispersion photoelectric and photographic spectra have been obtained for the short period variables δ Set, δ Del and p Pup over at least one cycle of variation.

An analysis of 1973 RT Andromedae B and V light curves is presented. The results are fitted into a spot evolution sequence found in a previous study which used the same technique on different data. The new values of the system’s physical parameters are in general agreement with the earlier ones.

The calculation of coupling coefficients for muon telescopes has previously used interpolation from a limited set of asymptotic directions of arrival of primary particles. Furthermore, these calculations have not incorporated curvature of the atmosphere and thus diverge from the true response at zenith angles greater than about 75 degrees. The necessary extensions to calculate coupling coefficients at arbitrary zenith angles are given, including an improved method of incorporating the asymptotic directions of the primary particles. It is shown, using this method, that certain coupling coefficients are highly sensitive to small changes in asymptotic directions for some telescope configurations.