Oxygen abundances for a large sample of dwarf stars in the Galactic thin and thick disks are determined from a non-LTE analysis of the oxygen triplet lines at 777 nm. Kinematic criteria are employed to determine whether a star belongs to the thin or thick disk. Temperatures are obtained from photometric calibrations based on the infrared flux

Aims: We present parallaxes of 11 mid-to-late T dwarfs observed in the UKIRT Infrared Deep Sky Survey. We use these results to test the reliability of model predictions in magnitude-color space, determine a magnitude-spectral type calibration, and, estimate a bolometric luminosity and effective temperature range for the targets. Methods: We used

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We obtained at the same time G-band images at the Dutch Open Telescope (DOT) on La Palma and spectropolarimetric data in the near infrared at the German Vacuum Tower Telescope (VTT) on Tenerife. The spectropolarimetric data show interesting correlations. Bright filaments have a smaller magnetic field s trength, and higher Evershed velocities occur

We report the results of a multisite observing campaign of observations of OJ287 in the visible, near infrared and submillimetric in Winter 1989-90. Simultaneous UBVRIK and white light data were obtained with three telescopes in Tenerife and La Palma on three nights in December-January, supported by follow-up observations in January and March 1990

The two main perturbative schemes for the non-linear evolution of large-scale structures are the Lagrangian and the Eulerian ones. The former has been set as a much more powerful technique, due to its property of yielding the exact solution in the plane-symmetric case. We have applied the Eulerian scheme to this plane symmetric case and have