The international Virtual Observatory (VO) is entering its operational phase. It is recognised at all levels, and particularly by the International Virtual Observatory Alliance (IVOA), that take-up of VO standards and tools by the scientific community must be the highest priority for each VO initiative. In particular, within the Euro-VO-AIDA EU/FP7 project, the Board and the Science Advisory Committee consider essential the dissemination, to each individual Member State of the project, of all the information allowing scientists to use the VO infrastructure.

A day-and-a-half course devoted to the VO, called VO-day, has been therefore organised for the Italian community, in the framework of the Euro VO-AIDA project and of the coordination initiatives at the international (IVOA) and national (VObs.it) levels. The course will be held at the locations specified below, with the support of INAF-OATs and INAF-SI, and in collaboration with the INAF structures and some Italian Universities.

The VO is opening up new ways of exploiting the huge amount of data provided by the ever-growing number of ground-based and space facilities, as well as by computer simulations. The goals of the workshop are to expose to the astronomers to the variety of VO tools and services available today so that they can incorporate them efficiently in their everyday research activities. The VO-day is open to all astronomers, in particular to young university graduates, doctorates and post-docs.

VO experts from the EURO-VO projects will first give some highlights on the usage of the tools. Real life examples of scientific applications will then follow. A large fraction of the time will be dedicated to hands-on exercises, which will allow participants to become fully familiar with the VO capabilities.

Tools providing the following functionalities will be presented:

• Image and spectra handling
• Catalogue and table handling
• Cross-correlations
• Data discovery and data mining
• Access to theoretical model

Additionally outreach and education activities using VO data and tools (WP5 of the VO-AIDA project led by INAF) may be presented.