The star formation history of the dwarf elliptical galaxy NGC 185, together with its spatial variations, has been investigated for old, intermediate-age, and young stars, using new ground-based Hα and BVI photometry and synthetic color-magnitude diagrams (CMDs). We find that the bulk of the stars were formed in NGC 185 at an early epoch of its

We present a quantitative analysis of the star formation history (SFH) of the Local Group dSph galaxy Leo I, from the information in its Hubble Space Telescope [(V-I),I] color-magnitude diagram (CMD). It reaches the level of the oldest main-sequence turnoffs, and this allows us to retrieve the SFH in considerable detail. The method we use is based

We have carried out broad band photometry of the interacting galaxy system NGC 6090 from 3.6 to 200μm using ISOPHOT. This is complemented by a low resolution spectrum in the wavelength range 2.5-11.5μm. The IR spectral energy distribution of a starburst galaxy is shown with unprecedented detail. From our Far Infrared measurements we can demonstrate

The stellar content and stellar age distribution of the Pegasus Dwarf Irregular Galaxy are discussed in the light of deep CM diagrams for (V - R) and (V - I) color indices, complemented by Hα data. The CM diagrams of Pegasus show two structures-red tail and red tangle-which denote the presence of intermediate-age and old stars in the galaxy. After

Since the early 1970s, stellar population modelling has been one of the basic tools for understanding the physics of unresolved systems from observation of their integrated light. Models allow us to relate the integrated spectra (or colours) of a system with the evolutionary status of the stars of which it is composed and hence to infer how the

Using a large amount of data gathered during previous seeing campaign at ORM, we analyse the temporal evolution of seeing in order to find out whether predictions could be made over a short time interval of a few hours. The first results are presented.