In recent years there has been some progress towards detecting solar-like oscillations in stars. The goal of this challenging project is to analyse frequency spectra similar to that observed for the Sun in integrated light. In this context it is important to investigate what can be learned about the structure and evolution of the stars from such

Ongoing spectroscopy and photometry of stars selected in the HK objective-prism/interference-filter survey of Beers and colleagues has resulted in the identification of many hundreds of additional stars in the halo (and possibly the thick disk) of the Galaxy with abundances [Fe/H]

It is now well established that there is a diffuse ionized medium which extends far beyond the discs of spirals. The mechanism responsible for the ionization is still an issue of debate, and the method of measuring the total luminosity, independently of the observational set-up, has to be defined. Here we analyse the case of the Magellanic

Long slit spectrophotometry of 13 bipolar planetary nebulae has been used to study their physical and chemical properties. In each nebula, one to seven different spatial regions have been considered in order to search for possible abundance variations through the nebulae. We obtained the following main results: - within the errors, the He, O, and N

There are two principal problems in explaining, in terms of the emission from OB stars, the ionisation of the gas which emits the diffuse H-alpha in spiral galaxies. One is the long pathlengths which the ionising photons need to traverse to reach their objectives, the other is whether sufficient photons can escape from within the HII regions which

Different estimates of the vertical gradient of magnetic field inclination in penumbrae disagree by 2 orders of magnitude. This disagreement may be resolved if measuring with typical angular resolutions implies averaging hundreds of independent fibrils whose residual variation, upon spatial averaging, gives rise to the observed large-scale