ESA's advanced communication satellite, Artemis, is ready to be shipped to Tanegashima space centre in Japan for its launch by a Japanese H2A rocket on 1 February next year. Before leaving Europe, it will undergo a final series of functional checkout tests at ESTEC, ESA's space research and technology centre in Noordwijk, the Netherlands. ESA invites the media on Tuesday 26 September to a background briefing on this challenging project at which they have the opportunity to see the state-of-the-art spacecraft in the cleanrooms.
Artemis is not the conventional type of communication satellite. In particular it differs in one very important aspect: none of its payloads connects a fixed point on the Earth with other fixed points on the Earth. Instead:
Artemis will connect users on the ground with satellites in orbit via its radio frequency data relay payload. This dramatically increases communication time with spacecraft in low-Earth orbit. For instance, a scientist anywhere in Europe will be able, via Artemis, to monitor the status of an experiment on the International Space Station in real time and actively intervene. This payload will also enable ESA's next Earth observation satellite, Envisat, slated for launch in 2001 as well, to transmit its instrument data to the ground in real time.
Via its optical data relay payload, SILEX, Artemis can receive and re-transmit in real time images taken by Earth observation satellites such as the French SPOT-4. Data communication between satellites using an optical link (laser pulses) is a novelty in space and offers great advantages over conventional radio frequency systems.
With Artemis, a mobile user will be able to link up from anywhere in Europe, North Africa or the Middle East to any fixed user in the same area at very competitive prices. Large ocean areas are included in Artemis' coverage zone, allowing voice or data connections to land from the Mediterranean, the North Sea or the eastern part of the Atlantic Ocean.
- The navigation payload will enable users to determine their position with higher accuracy and 24-hour availability. Artemis will add corrections and health checks to the existing GPS signals, thus supporting the first phase of Galileo, Europe's new navigation programme.
In addition to these many novel communication services Artemis will provide European industry with opportunities to gain in-orbit experience with advanced technologies. The most prominent of these is the ion propulsion system. Its very high power-to-mass ratio helps to reduce launch cost and increase satellite lifetime.