Below is an excerpt from the webs. It landed on 2012. Sort of confusing their numbers. Power system designed to last two years. Estimated life span of components is 5 to 6 years (so to 2018 or so). But all the components were tested to 3x that length of time. But then farther down they mention the power plant, which can last 10 to 15 years.
Anyway - I think we got our money’s worth!
Excerpt:
While the rover could realistically survive five or six years on Mars, there are three main areas that could limit Curiosity’s life: the rover’s onboard mechanisms, its batteries, and its nuclear-powered RTG, he explained.
“We test the mechanisms usually for three times life — sometimes two — and we don’t test them to failure,” Theisinger told SPACE.com. “So, all the mechanisms have been tested to last two to three times longer than we expect the mission to operate, if they haven’t failed in that period of time.”
The rover’s batteries and RTG are designed to operate on Mars for at least 687 Earth days, but could endure for longer. [Infographic: History of Robotic Red Planet Missions]
“The RTG suffers from the degradation of plutonium dioxide, but that lasts a long time,” Theisinger said. “I think from the RTG, I would expect to get 10, 12 or 15 years out of it.”
“The RTG suffers from the degradation of plutonium dioxide, but that lasts a long time,” Theisinger said.
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It keeps glowing, and glowing, and glowing!