Europe’s primary Earth-observation satellite has gone silent.

Europe’s primary Earth-observation satellite, Envisat, has gone silent.

Launched in 2002, the satellite is billed as the most sophisticated environmental monitor in orbit, with ten instruments providing streams of valuable data on everything from ozone, clouds and greenhouse gases to land-use trends and sea-surface temperatures — data that have figured in more than 2,000 scientific publications, ESA says. Over the years, Envisat has also offered a unique vantage point on major environmental disasters such as the December 2004 earthquake and tsunami in southeast Asia and the Deepwater Horizon oil spill in the Gulf of Mexico in 2010. Now, scientists fear that the satellite’s decade-long run has come to an abrupt end.

Problems began on 8 April when the satellite’s signal cut out as it was passing over a ground station in Sweden. ESA has been working with a team of scientists and engineers to diagnose the problem and to re-establish contact, but the outlook remains unclear.