The 1.5 m telescope GREGOR opens a new window to the understanding of solar small-scale magnetism. The first light instrumentation includes the Gregor Fabry Pérot Interferometer (GFPI), a filter spectro-polarimeter for the visible wavelength range, the GRating Infrared Spectro-polarimeter (GRIS) and the Broad-Band Imager (BBI). The excellent

The steep abundance gradient found by McCall, Shields, and Rybski (1981) in the Sbc galaxy NGC 3344 is confirmed by a measurement of the electron temperature in the outer H II region.

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An analysis of CCD spectra in the range lambda lambda4200 -8775, obtained at several positions of seven bright Galactic H Ii regions, with galactocentric distances in the range 6-10 kpc, is presented. Temperatures, densities and ionic abundances are calculated for all the positions, and the relative trends followed by these parameters are

The age decay of two indicators of the stellar magnetic activity (λ2800 Mg II emission flux and λ10830 He I equivalent width) have been studied for field solar-type stars. The Li abundance has been used, in most of the cases, as a stellar age indicator. A calibrated decay law for Mg II has been determined and compared with a similar one, recently

The measurement of the structure of stellar populations in the Milky Way disc places fundamental constraints on models of galaxy formation and evolution. Previously, the disc's structure has been studied in terms of populations defined geometrically and/or chemically, but a decomposition based on stellar ages provides a more direct connection to