Sirio (Satellite Italiano di Ricerca Industriale e Operativa, Italian Satellite for Industrial Operative Research) is an experimental, geostationary artificial telecommunication satellite, the first to be designed and manufactured in Italy. It was launched on August 26th, 1977, from the American base of Cape Canaveral, aboard the NASA Delta 2313 vector.
The main purpose of this satellite, a cylinder with a 143 cm-diameter and a 229 kg-weight, covered with solar cells, was experimenting high-frequency propagation, up to 18 Ghz.
Sirio was born from the cooperation between the National Research Council and the Aerospace Industry Company – a consortium which brought together the main companies in this industry, and was designed to have an operating life of two years, but it remained active for eight years, until 1985.
The satellite was at the core of several experimental activities on the propagation phenomena and frequency bands, and was used also to carry out tests on TV communication. Such experiments were carried out by Italian and international research centres.