Galileo - technical definition

A satellite-based radio navigation system initiated by the European Union and European Space Administration (ESA). Using 27 satellites and three spares, Galileo is expected to be completed by 2011 and be interoperable with the United States GPS and Russian GLONASS systems. Positioning accuracy is expected to be brought down to one meter (GPS is 20m; GLONASS is 60m). The first Galileo satellite (GIOVE-A) was launched in late 2005. For more information, visit http://europa.eu.int/comm/dgs/energy_transport/galileo. See GNSS and GPS.