The European Space Agency is to propose to its member states a European data relay satellite system (EDRSS) that could be a constellation of up to three spacecraft in geostationary orbit, with the first to be launched in 2012.

NASA's Tracking and Data Relay Satellite System (TDRSS), used for telecommunications for the International Space Station and its scientific missions, will be used by ESA's Automated Transfer Vehicle cargo ship. The arguments in favour of ESA establishing its own relay system are that it would aid European independence and guaranteed access to space with the real-time tracking of launchers over oceans and improve the reliability and security of Galileo's augmentation system, the European Geostationary Navigation Overlay Service.

As well as data transfer for ISS utilisation and future ATV operations, the EDRSS could also be dual use, providing services to European armed forces. The EDRSS project proposal is to be discussed at the next ESA navigation and telecoms programme board as part of the preparation before the November member state ministerial council.

"This will be submitted in November. It is open for subscription. We are doing studies, pre-pre-phase A, they are user-driven studies. Some technological development is also necessary," says ESA telecoms and navigation department head of strategy and future payloads, Ralth Bierett.

If EDRSS were approved at the November council the spacecraft could be developed in time to work with the satellites being produced for the Global Monitoring for Environment and Security programme (GMES). The first of the five spacecraft for GMES, the Thales Alenia Space-built Sentinel-1, is to be launched in 2012.

ESA is already using its Artemis satellite for data transfer and this spacecraft was only to be a technology demonstrator. Once Bierett's study has defined the user needs, a system of governance will also be developed for what is hoped will be a public-private partnership model with a commercial operator selling data transfer to institutions and private customers.

Source: Flight International