The solar cycle was studied by considering only the large active regions (AR), with small region data being ignored. Results show that at birth almost all the large AR display the correct inclination (p-part at lower latitude) while the small AR show random behavior. The maximum latitude attained by the large AR is lower by 10 deg than that of the

It is reported that 8-13-micron spectra have been obtained at several positions across the extended emission region of M82. No major differences among the spectra are found. In addition, a strong similarity is found between these spectra and the infrared spectrum of the Orion ionization front. The data are interpreted using a model for M82 in which

The effect of scattering by dust internal to H II regions on their spectral characteristics has been studied on the basis of simple analytical models, for assumed universal optical parameters of the dust. A procedure to determine the external interstellar extinction and the internal gas to dust abundance ratio of H II regions has been developed and

A high resolution spectrum (Δλ = 0.2 Å) of the Population II star HD 76932 from the archive of the IUE satellite has been analysed in a search for measurable resonance absorption lines due to 9Be. Matching the observations by a synthesized model of the wavelength region around the doublet at 3130 Å gives a conservative upper limit for the abundance

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Observations carried out with a 8-13 micron grating-spectrometer of Mrk 231 and NGC 4151 are reported. The Mrk 231 data can be fitted to various thermal dust emission models or a single power law, with dust extinction. In all the model fits, except for that of graphite and silicon carbide grain emission, a component of silicate absorption of