Multifrequency Catalogue Of Blazars 0h-6h

Present and near-future space and ground–based observatories are bound to provide large amounts of fresh multi-frequency data on many Blazars, a wealth of information that can be fully exploited only if properly handled within well organized databases. The first step in this direction is to build an updated and carefully checked list of all known Blazars and this is the main motivation behind this Blazar Catalogue. Our catalogue is not just a simple list of sources, as we report fluxes in different energy bands and detailed Spectral Energy Distribution for a selection of well–studied Blazars. In this first volume we concentrate on Blazars with Right Ascension between 0h:00 to 6h:00. Three more volumes will follow in the near future with the aim of completing the entire sky by the end of 2006. Blazars will almost certainly be important observational targets for the next generation of space missions like AGILE, GLAST, and will be detected in large numbers by PLANCK. This catalogue should therefore be considered also as a contribution to the activities carried out in preparation for these upcoming space observatories