We classify non-trivial (non-central) extensions of the group $Diff^+(S^1)$ of all diffeomorphisms of the circle preserving its orientation and of the Lie algebra $Vect (S^1)$ of vector fields on $S^1$, by the modules of tensor-densities on $S^1$. The result is: 4 non-trivial extensions of $Diff^+(S^1)$ and 7 non-trivial extensions of $Vect (S^1)$

The advent of large 8-10m telescopes heralds a new age in stellar astronomy. It is now possible to carry out detailed spectroscopic observations at high resolution of the brightest stars of galaxies in the Local Group, and it is envisaged that intermediate resolution observations will be extended to stars in the nearest galaxy clusters such as

Aims:We investigate the statistical properties of the extreme events of the solar cycle as measured by the sunspot number. Methods: The recent advances in the methodology of the theory of extreme values are applied to the maximal extremes of the time series of sunspots. We focus on the extreme events that exceed a carefully chosen threshold and a

IAUC 4252 available at Central Bureau for Astronomical Telegrams. IAUC 4252 available at Central Bureau for Astronomical Telegrams.

The Gran Telescopio Canarias (GTC1) 10m telescope is now being integrated at the ORM, in La Palma Spain. Likewise, three instruments are being prepared for first light and, as of this writing, are about to start their laboratory integration. These first light instruments are: 1) OSIRIS, a large field of view imager and multi-object spectrograph

Until April 2007 the Major Atmospheric Gamma ray Imaging Cherenkov (MAGIC) telescope used a 300 MSamples/s flash analog-to-digital converter (FADC) system to sample the shaped photomultiplier tube (PMT) signals produced by the captured Cherenkov photons of air showers. Different algorithms to reconstruct the signal from the read-out samples