GEOSTAR: a technical overview of the first European seafloor observatory

Between 2000 and 2001, the multidisciplinary seafloor observatory GEOSTAR, developed in the framework of a European project, successfully carried out the first long-term deep-sea mission in the Southern Tyrrhenian Sea at the depth of 2000 m offshore Ustica Island. During the mission, scientists and engineers could get real-time continuous access to the deep-water environment. Around seven months of scientific data were collected, opening the road to the development of submarine networks of seafloor observatories. The scope of this paper is to give a technical overview of GEOSTAR, describing, in particular, the system architecture, the main features of its components and the peculiarities of the concept with respect to the experiences so far developed worldwide.