The authors have obtained high-resolution spectrograms of H-rich central stars of planetary nebulae (CSPN) with the 3.6 m telescope and Cassegrain echelle spectrograph of the European Southern Observatory. They have determined the basic atmospheric parameters (Teff, log g, photospheric He abundance) for 22 of these CSPN, by fitting the observed

The galactic evolution of the abundances of the light-element isotopes (6Li, 7Li, 9Be, 10B, and 11B) is re-examined in view of recent measurements of the 7Li/6Li interstellar isotopic ratio. The high value of this ratio (≡40), found by Ferlet and Dennefeld (1984) towards ζ Oph, can be reproduced by simultaneously including contributions to the

U,B,V,R,I and simultaneous near infrared J,H,K light curves of the RS CVn system ER Vul are presented. A study of the mean levels compared to other years indicates that the system is highly variable, giving evidence that important changes occur over one month. Colours show an ultraviolet and infrared excess. There seems to be a contribution from a

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Measurements of the line of sight velocity of the sun with respect to earth have been obtained at Izaña (Tenerife) during the years 1976 to 1985. The mean values found for each year show a trend of ≡30 m/s from minimum to maximum. Their mean value is of 583.1±0.2 m/s which is 92% of the gravitational redshift predicted by theory and their variation

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