On March 21st, a replenishment satellite for the EGNOS service will leave the European SpacePort of Kourou aboard an Ariane 5 launcher. This will ensure a next 15 years of uninterrupted EGNOS service above Europe.
The launch window will open at 10.05 PM (UTC) and close at 11.14 PM (UTC).
EGNOS, the European Geostationary Navigation Overlay Service, is a Satellite-Based Augmentation System (SBAS) that improves the accuracy and provides integrity to the GPS signal over most of Europe.
SBAS systems are designed to augment the navigation system constellation by broadcasting additional signals from geostationary (GEO) satellites; they provide differential correction messages and integrity data for the GPS satellites which are in the view of a network of monitoring stations, taking into account signal distortions provoked by factors like the ionosphere, and which could seriously impair the precision of the localisation (picture © Arianespace).
EGNOS is owned by the European Commission and was launched in 2009 to be part of the Galileo global satellite navigation system. The European Space Agency designed EGNOS under a delegation agreement with the Commission.
EGNOS is the first pan-European satellite navigation system. Similar services are provided in North America by the Wide Area Augmentation System (WAAS), in Japan by the Multifunctional Satellite Augmentation System (MSAS) and in India by the GAGAN System. Other similar Satellite Based Augmentation Systems (SBAS) are under study or development in other regions of the world.
As from January 1st, 2014, EGNOS is operated by the European GNSS Agency (GSA) based in Prague.