Envisat satellite goes silent

Nature : Envisat, the European Space Agency’s (ESA’s) most sophisticated environmental monitor, has stopped sending data to Earth. Its signal cut out when it passed over a Swedish ground station on 8 April, although it’s still in stable Earth orbit. Launched in 2002, it has doubled its intended life of five years, providing data on ozone, clouds, greenhouse gases, land-use trends, and sea-surface temperatures. Most of its instruments have analogues on other satellites, but ESA had planned to overlap Envisat with the Sentinel satellite series flying under the Global Monitoring for Environment and Security (GMES) program. GMES was scheduled to begin operations 2013–14, but longer-term funding commitments for the program still need to be negotiated. ESA’s mission control is working to reestablish contact with the satellite.