The plucky Mars rover, Spirit, was officially declared out of commission on Wednesday after seven and a half years of exploring the red planet, according to dpa. NASA said it had sent its very last attempt to communicate with Spirit, after ten months of trying, and would now turn its full attention to the next generation Mars rover, Curiosity. Spirit last phoned home on March 22, 2010, and, by July, NASA had just about given up on ever hearing from it again. But it still launched a 10-month-long series of attempts to reawaken the vehicle. That came to an end on Wednesday. "While we no longer believe there is a realistic probability of hearing from Spirit, the Deep Space Nrtwork may occasionally listen for any faint signals when the schedule permits," said Dave Lavery, NASA's director of solar system exploration. Spirit has already far exceeded its original lifetime expectancy of 90 days, from when it landed on Mars in 2004. With battery power running low and sapped even more by the lack of sunlight to recharge during the "stressful Martian winter," NASA said Spirit has "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," NASA said. Spirit's twin, Opportunity, which landed on Mars just weeks after Spirit in January 2004, continues active exploration of the planet, also long past its 90-day expiration date. Curiosity, a laboratory project that weights five times as much as Spirit, is to be launched in November and land on Mars in August to explore if the planet is habitable for humans.
