"The warranty expired long ago on NASA's twin robots motoring around Mars. These two golf cart-sized vehicles were only expected to last three months.
In two years, they have traveled a total of seven miles. Not impressed? Try keeping your car running in a climate where the average temperature is 67 below zero and where dust devils can reach 100 mph.
'These rovers are living on borrowed time. We're so past warranty on them,' says Steven Squyres of Cornell University, the Mars mission's principal researcher. 'You try to push them hard every day because we're living day-to-day.'
The rover Spirit landed on Mars on Jan. 3, 2004, and Opportunity followed on Jan. 24. Since then, they've set all sorts of records and succeeded in the mission's main assignment: finding geologic evidence that water once flowed on Mars."