Mars rover Opportunity completes first ‘marathon’ on another world

How long does it take to complete a marathon on Mars? About 11 years and two months – if you’ve got six wheels and a solar-powered battery.

NASA’s spunky rover Opportunity crossed the Olympic marathon mark on Tuesday, putting 26.219 miles on its odometer during its 3,968th Martian day. (A Martian day, or sol, is about 39 minutes and 35 seconds longer than an Earth day.)

While that time wouldn’t come close to breaking land-speed records on Earth, it certainly qualifies anywhere else.

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

In July, NASA announced that Opportunity had broken the otherworldly driving distance record held by Lunokhod 2, a rover sent to the moon by the Soviet Union in 1973.


Opportunity and its twin rover, Spirit, touched down on opposite sides of the Red Planet back in January 2004. At the time, Beyonce’s “Me, Myself and I” was at the top of the charts and “Along Came Polly” was in movie theaters.

The two members of the Mars Exploration Rover mission were tasked with studying the Martian terrain to understand how water once shaped the now-barren planet. Opportunity was sent to Meridiani Planum, a plain near the equator with an ancient layer of the mineral hematite. On Earth, the iron oxide mineral forms in the presence of water.

It took less than six weeks for Opportunity to find convincing evidence that Mars indeed had a watery past. The proof came in the form of rocks full of sulfate salts, NASA scientists said.

Opportunity’s initial mission was expected to last just 90 sols (about 92.5 Earth days) and take the rover a mere 0.6 miles from its landing site. NASA has extended Opportunity’s mission multiple times, and it is now working on the west rim of Endeavour Crater, where clay minerals could hold signs that ancient Mars was not only wet but suitable for microbial life.

Opportunity’s current location overlooks a Martian gorge that NASA has named Marathon Valley.

Here on Earth, employees at JPL plan to celebrate Opportunity’s milestone by holding a marathon-length relay at the NASA lab in La Canada-Flintridge.

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