Envisat formally declared lost

The European Space Agency (ESA) has formally declared that the Envisat environmental and remote sensing satellite mission is now over, following the satellite\'s 8 April loss of contact and subsequent failure to reestablish it. The attempt at fault finding and recovery included ground radar and telescopes on Earth and Pleiades imaging satellites in space. Despite efforts, controllers were unable to reestablish contact. An internal power regulator failure or short circuit is currently suspected of causing the sudden failure of the telemetry and command system or its safe mode solar pointing default procedure, failures that are uncorrectable from the ground. Despite the formal ending of the mission, engineers will continue to investigate the failure and carry on with attempts to recontact the craft. Launched in March 2002, Envisat exceeded its five year minimum design life by over five years. During its ten year life the spacecraft has yielded valuable Earth monitoring data covering weather, atmospheric and temperature measurements as well as providing optical and infrared imagery. Concerns remain within the climate change science community that the dataset will now be significantly interrupted until ESA\'s new Sentinel spacecraft from Europe\'s Global Monitoring for Environmental Security (GMES) programme comes online.