We present the results of the optical photometric observations of the Pleiades (125 Myr) cluster. The aim of this research is to look for variability, both due to rotation of single stars and the presence of eclipsing binaries. We have used differential photometry and two different methods of statistical analysis of the data. We have found

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Aims: We study small-scale brightenings in Ca II 8542 Å line-core images to determine their nature and effect on localized heating and mass transfer in active regions. Methods: High-resolution two-dimensional spectroscopic observations of a solar active region in the near-infrared Ca II 8542 Å line were acquired with the GREGOR Fabry-Pérot

We discuss the status of the calibration programme for CanariCam and related initiatives that aim to provide quality calibration facilities for users of the GTC and other telescopes. We have Visible and IR photometry of >300 stars apt for the calibration of CanariCam giving an initial density of ~ 1 star per 100 square degrees of sky. The

We describe an ongoing effort to validate the estimated atmospheric parameters (Teff, log g, [Fe/H]) obtained from SDSS spectroscopy (R = 2000) and ugriz photometry, which are being employed for both the previous SDSS-I and the ongoing SEGUE surveys. The spectroscopic pipeline makes use of a number of methods for the estimation of each parameter