The new launch will take place within a year of the flight of the first two Galileo In-Orbit Validation satellites, which reached orbit on 21 October 2011.
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Galileo IOV in orbit |
Four navigation satellites represent the minimum needed for satellite navigation – to measure latitude, longitude and altitude while checking ranging accuracy – so these four Galileo IOV satellites can be used to assess the performance of Galileo’s world-spanning ground system which serves to maintain the precision of the Galileo system.
In addition European industry should be able to realistically test their own prototype Galileo-based receivers and services against actual satellite signals.
About Galileo
Galileo is an initiative of the European Commission and ESA to provide Europe with an independent global satnav system. The Commission and ESA have signed a delegation agreement by which ESA acts as design and procurement agent on behalf of the Commission.
The full Galileo system will consist of 30 satellites in orbit overseen by control centres located in Europe and a global network of sensor stations and uplink stations.
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One of Galileo’s next batch |
Each satellite combines the best atomic clock ever flown for navigation – accurate to one second in three million years – with a powerful transmitter to broadcast precise navigation data worldwide.
The Galileo programme is structured in two phases, with the initial In-Orbit Validation phase consisting of deployment tests and the operation of four satellites and their associated ground infrastructure. This is followed by the Full Operational Capability (FOC) phase, consisting of the deployment of the remaining ground and space infrastructure.
The definition phase and the development and In-Orbit Validation phase of the Galileo programme were carried out by ESA and co-funded by ESA and the European Commission.
The Full Operational Capability phase of the Galileo programme is managed and fully funded by the European Commission. The Commission and ESA have signed a delegation agreement by which ESA acts as design and procurement agent on behalf of the Commission.
