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Mars rovers still exploring Red Planet
The warranty expired long ago on NASA's twin robots motoring around Mars. In two years, they have traveled a total of 11 kilometers.
The warranty expired long ago on NASA's twin robots motoring around Mars. In two years, they have traveled a total of 11 kilometers. Not impressed? Try keeping your car running in a climate where the average temperature is 67 below zero and where dust devils can reach 161 kph.
These two golf cart-sized vehicles were only expected to last three months.
"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 January 3, 2004, and Opportunity followed on January 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.
Part of the reason for their long survival is pure luck. Their lives were extended several times by dust devils that blew away dust that covered their solar panels, restoring their ability to generate electricity.
Like most Earth-bound vehicles, these identical robots have their own personalities.
The overachieving Opportunity dazzled scientists from the start. It eclipsed its twin by making the mission's first profound discovery - evidence of water at or near the surface eons ago that could have implications for life.
The rock-climbing Spirit went down in the history books by becoming the first robot to scale an extraterrestrial hill. Last summer, it completed a daredevil climb to the summit of Husband Hill - as tall as the Statue of Liberty - despite fears that it might not survive the weather.
