Opportunity rover: 9 years on Mars

Today is the 9th anniversary of the Mars landing of the NASA rover Opportunity, ABC News reported.

When Opportunity dropped onto the Red Planet just after midnight EST on Jan. 25, 2004, NASA scientists crossed their fingers that the rover would last 90 days in the Martian landscape, ABC News reported.

Nine years later, all of its six motorized wheels are still working, and the rover has driven 22.03 miles, ABC News reported.

"Opportunity is still in very good health, especially considering what it's gone through," John Callas, manager of NASA's Mars Exploration Rover project, told ABC News. “The surface of Mars is a pretty tough place; there can be temperature fluctuations of a hundred degrees each day. That's pretty hard on the hardware."

Spirit, another Mars rover launched around the same time, also far exceeded longevity expectations, finally breaking down in March 2010, CBS News reported.

Scientists had expected that Martian dust would accumulate on Opportunity’s solar panels, reducing its ability to gather electricity over time, but regular wind gusts keep blowing off the dust, ABC News reported.

Opportunity is currently at a place called Matijevic Hill, investing veins of calcium sulfate in the rock there, Mars Exploration Rover Principal Investigator Steve Squyres of Cornell University told CBS News. “It's really, really compelling evidence for water flowing through fractures,” he said.

“We voided the warranty on this thing so many years ago that we just sort of treat every day as a gift at this point,” Squyres told CBS News. “We're just pushing it as hard as we can right now and trying to squeeze everything out of it we can. So no guarantees. But right now, the vehicle's in great shape. The vehicle's healthy, we're doing good science and lots of good stuff is happening.”

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