Spirit is officially dead. NASA says it will stop trying to wake up the little Mars rover, which has been silent since March of 2010.
Spirit's twin rover, Opportunity, continues to explore its patch of the Martian surface. The rovers had been working extreme overtime for years—Spirit landed in 2004 for what was supposed to have been just a three-month mission but kept rolling until March 2010.
NASA said a cold, dark Martian winter likely did Spirit in.
"With inadequate energy to run its survival heaters, the rover likely experienced colder internal temperatures last year than in any of its prior six years on Mars. Many critical components and connections would have been susceptible to damage from the cold," the space agency said in a statement.
"We're now transitioning assets to support the November launch of our next generation Mars rover, Curiosity," said Dave Lavery, program executive for solar system exploration.