Mars Global Surveyor

Mars Global Surveyor was launched in 1996 on a mission designed to study Mars from orbit for two years. It accomplished many important discoveries during nine years in orbit. On Nov. 2, 2006, the spacecraft transmitted information that one of its arrays (---> pannelli) was not pivoting (--> ruotando) as commanded.
Loss of signal from the MGS Orbiter began on the following orbit.

Mars Global Surveyor has operated longer at Mars than any other spacecraft in history and for more than four times as long as the prime mission originally planned.

NASA has recently formed an internal review board to look more in-depth into why NASA's Mars Global Surveyor went silent in November 2006 and recommend any processes or procedures that could increase safety for other spacecraft.