The workhorse of the European Space Agency’s earth observation initiative went silent over the weekend, and the agency admits today that it hasn’t heard a beep from the aging satellite since Sunday. The nearly-nine-ton spacecraft is in a stable orbit, but if the problem persists the ESA may have to finally retire Envisat, which has been in orbit twice as long as it was designed to be.
ESA’s mission control first called a spacecraft emergency on Sunday when the spacecraft unexpectedly went silent as it passed over a ground station in Sweden. Since then, the ESA has requested help from ESA tracking stations across the globe, but so far the satellite remains uncommunicative.
The team is still trying to re-establish contact, but if it cannot the ESA stands to lose one of the world’s most sophisticated Earth observation satellites. Envisat’s 10 instruments provide data on land masses, sea ice, atmosphere, and ocean conditions. In terms of its mission, Envisat has long outlasted it’s packaged expiration date, which came and went back in 2007 (Envisat launched in 2002).
But from a capabilities standpoint, losing Envisat would mark a setback for the ESA’s ongoing earth science program. The agency had hoped the satellite would remain in service until 2014, by which point the first of its Sentinel satellites–the successors to Envisat’s mission–would be in orbit. The first of those satellites is slated for launch next year, but the ESA hoped to have both Envisat and that first Sentinel in service for a period of overlap so they could calibrate their data. As things stand this morning, the ESA could instead be facing a bit of a science gap until the Sentinel missions get underway.