David Shiga writes, "NASA's silent Mars Global Surveyor (MGS) spacecraft is likely lost forever. The space agency attempted to take a picture of the 10-year-old spacecraft using the newer Mars Reconnaissance Orbiter, but did not detect it, either because its orbit has shifted since last contact, or because it isn't reflecting enough sunlight to be visible. NASA has now ordered its Opportunity rover to listen from the planet's surface for MGS's radio beacon. If that fails, the agency may call on the European Space Agency's Mars Express spacecraft to join the search. But MGS may already have run out of power and NASA officials are not optimistic about recovering it."