Europe’s largest and most complex Earth observation satellite, the ENVIronmental SATellite, Envisat, was launched in 2002 by an Ariane 5 into an 800-km polar orbit. This European Space Agency satellite is helping scientists gain a better understanding of the effects of global warming, El Niño, climatic changes and the depletion of the ozone layer, as well as variations in ocean-levels, ice caps, vegetation and the composition of the atmosphere.

Development and construction of the 8,200 kg spacecraft took more than 10 years, and involved almost 100 companies in 14 countries. Astrium sites in the UK, Germany, Spain and France all participated in the programme: Astrium UK was the prime contractor for the Polar Platform and two of the major instruments; Astrium Germany held overall responsibility for the instruments, the payload equipment bay and two instruments; Astrium Spain was responsible for the structure and Astrium France supplied the service module and other instruments.

The Envisat mission has been extended through to 2013. Envisat can deliver near real time data which makes it possible to provide daily sea surface temperatures, worldwide fire maps, UV radiation levels and ozone forecasts, all accessible in the internet. The long mission lifetime also give scientists access data over long periods of time in order to allow the identification and analysis of long-term climatic trends and changes (such as greenhouse gas concentrations, sea surface temperature, sea levels, sea-ice extent).