We present high quality spectroscopic data for two massive stars in the OB 10 association of M31, OB 10-64 (B0 Ia) and OB 10-WR1 (WC6). Medium resolution spectra of both stars were obtained using the ISIS spectrograph on the William Herschel Telescope. This is supplemented with Hubble Space Telescope STIS UV spectroscopy and Keck I HIRES data for

We present the results of hydrodynamical model calculations of the barred galaxy NGC 5850 and compare to HI observations. The models assume a mass distribution for the galaxy which was obtained from photometrical I band observations. A pure bar perturbation model reproduces the HI observations in the inner 80'' of the galaxy. The reproduced

We present observational evidence for a galaxy ``type'' dependence to the location of a spiral galaxy's disk parameters in the μ0-logh plane. With a sample of approximately 40 low surface brightness galaxies (both bulge- and disk-dominated) and approximately 80 high surface brightness galaxies, the early-type disk galaxies (=Scd) spiral galaxies

As long as the yellow hypergiant HR8752 has been observed spectroscopically it has shown erratic and significant fluctuations in its effective temperature. But an impressive and hitherto never observed rise in its temperature started around 1985. Since that time Teff has risen from 4600 K to 7900 K. Regular further observations are needed to see if

The Wide Field Imager instrument of the MPG/ESO 2.2-m Telescope has been operating with the VLT-style Observing Software (OS) since the beginning of the year. Users can now prepare Observation Blocks in the same manner as for the VLT and other La Silla instruments. This uniformity of the user interface will make the system even more easy to use

We compute photoionization models for the giant extragalactic H II region NGC 5461 and compare their predictions to several observational constraints. Since we aim to reproduce not only the global properties of the region but also its local structure, the models are constrained to reproduce the observed density profile, and our analysis takes into