The authors have analyzed far-IR (IRAS) data for a sample of optically selected Seyfert galaxies. The far-infrared emission is uncorrelated, or at best weakly correlated, with the UV-optical emission from these sources. The authors find the far-IR emission to be extended in a number of objects. They discuss the possibility that Seyfert galaxies are

Details of the present work will be published in Rev. Mexicana Astron. Astrofis.

Four main aspects of umbral and penumbral fine structures are considered: brightness and morphology, magnetic field, velocity and oscillations. The author discusses a model in which penetrative convection produces peripheric umbral dots and upward flowing matter which is channeled outwards, pushing the magnetic field aside. The possibility of a non

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High resolution (better than 1arcsec) magnetograms obtained at the Sacramento Peak Vacuum Tower Telescope were used to study the decay of a small active region. The reduction process allows one to match intensity and magnetic pictures exactly.