The lithium abundance in 26 T Tauri stars is derived using data taken at the Isaac Newton Telescope and data from literature. The aim is to understand the mechanisms leading to lithium depletion in the premain sequence phase, which, in turn, can provide useful information on the convective structure of premain sequence objects.

The new results of the Jodrell-IAC Cosmic Microwave Background (CMB) anisotropy experiment for declination +40 deg are presented. A similar level of sensitivity has been achieved with respect to the reported previous experiment at an angular scale of 8.8 deg in Davies et al. (1987). A positive temperature deviation of roughly 0.3 mK at 10.46 GHz is

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The radiation of light from matter rotating in the vicinitiy of compact objects (neutron stars or black holes) is expected to be affected from significant frecuency shifts which are two-fold in origin: (1) the velocity of rotation, in the inner parts of accretion disks, is of the order of the velocity of light, thereby producing Doppler shifts of

The shorter contributed papers are published in Astrophysics and Space Science, Vol. 156, Nos. 1 -2 (Jun 1989), Vol. 157, Nos. 1 - 2 (Jul 1989). Contents: 1. Preface. 2. Origin and early development of galaxies. 3. Gas and global star formation. 4. Galactic nuclei. 5. Population, age and dynamics of our Galaxy. 6. Supernovae and their effects. 7