The Little Rover that Could: Opportunity Reaches Odometer Milestone

NASA’s Opportunity mars rover now holds the off-Earth roving distance record after accruing 25 miles of driving. Given that the rover has been roaming the Red Planet for over a decade, that’s a travel speed of roughly 2.5 miles per year, and it’s one to be proud of.

“Opportunity has driven farther than any other wheeled vehicle on another world,” said Mars Exploration Rover Project Manager John Callas, from NASA’s Jet Propulsion Laboratory in a NASA press release. “This is so remarkable considering Opportunity was intended to drive about one kilometer and was never designed for distance. But what is really important is not how many miles the rover has racked up, but how much exploration and discovery we have accomplished over that distance.”

The previous record was held by the Soviet Union’s Lunokhod 2 rover, which landed on the moon in 1973. It drove about 24.2 miles in less than five months, according to calculations recently made using images from NASA’s Lunar Reconnaissance Orbiter.

“The Lunokhod missions still stand as two signature accomplishments of what I think of as the first golden age of planetary exploration, the 1960s and ’70s,” said Steve Squyres from Cornell University, and principal investigator for NASA’s twin Mars rovers. “We’re in a second golden age now, and what we’ve tried to do on Mars with Spirit and Opportunity has been very much inspired by the accomplishments of the Lunokhod team on the moon so many years ago. It has been a real honor to follow in their historical wheel tracks.”

A drive of 157 feet on July 27 put Opportunity’s odometer at 25.01 miles. The rover is currently headed southward along the western rim of Endeavour crater: a site that is continuing to yield evidence of ancient environments with less acidic water than those examined at Opportunity’s landing site.

If the rover can continue to operate for another 25.2 miles — the distance of a marathon — it will approach the next major investigation site: a valley, which scientists have dubbed “Marathon Valley.” Observations from spacecraft in orbit suggest that the valley is composed of a stack of layered sediments, offering a glimpse at the Red Planet’s changing geologic history.

Opportunity has continued to rove, gather scientific observations, and report back to Earth for over 40 times its designed lifespan. Now every additional mile reached will set the record for the longest off-Earth roving distance.