Rover finishes 11-year marathon on Mars

There is no such thing as too slow to run a marathon.

After all, it took a Mars rover about 11 years and two months to travel a marathon-length distance across the Red Planet.

NASA's Mars Exploration Rover Opportunity surpassed the marathon mark Tuesday, having traveled a distance of 26.2 miles on the surface of Mars.

"This is the first time any human enterprise has exceeded the distance of a marathon on the surface of another world," said John Callas, Opportunity project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif., in a statement.

The long-serving rover displaced the previous record-holder for the greatest distance traveled off-planet, the former Soviet Union's Lunokhod 2 moon rover.

"This mission isn't about setting distance records, of course; it's about making scientific discoveries on Mars and inspiring future explorers to achieve even more," said Steve Squyres, Opportunity principal investigator at Cornell University in Ithaca, N.Y., in a statement. "Still, running a marathon on Mars feels pretty cool."

Opportunity is one of two rovers that launched to Mars' surface in April 2004 by NASA. The other rover, Spirit, stopped communicating in 2010.

Opportunity completed its three-month prime mission and went on to discover evidence of liquid water on Mars throughout its explorations of the Eagle, Victoria and Endeavor craters.

This landmark represents yet another step in Opportunity's long-term mission of exploring the Endeavor crater, examinations of which have provided information about "ancient wet conditions less acidic, and more favorable for microbial life, than the environment that left clues found earlier in the mission," according to NASA.

To celebrate the achievement, the team at the Jet Propulsion Laboratory plans a marathon-length relay run at the lab next week.