article image

Rover marks 11th anniversary on Mars while battling memory problems

Elizabeth Howell, News Writer
Jan 24, 2015, 1:42 UTC

Sen—As Opportunity paused in its exploration of Mars to snap a new panorama from its vantage point on a crater rim, controllers at the Jet Propulsion Laboratory (JPL) are busily working on a memory fix for the 11-year-old rover.

Opportunity took a series of images from the summit of Cape Tribulation, the highest point that the rover has reached in years. But as the rover rolls towards a marathon's worth of driving on the Red Planet, controllers say problems with its Flash memory will require a long-distance update from Earth.

Flash memory is required to hold information when the rover sleeps, which the solar-powered machine does every night on Mars.

"The Flash memory degradation is causing multiple resets of the rover on each wake-up," NASA wrote in an update concerning the rover's activities up to 13 January. Controllers are instead using random access memory (RAM) to store information temporarily.

"Meanwhile, the project has developed the strategy to mask off the troubled sector of Flash and resume using the remainder of the Flash file system in normal operations. The project plans to implement the masking after an independent review is held later this week."


The full panorama that the Opportunity Mars rover took at Cape Tribulation on 6 January, 2015. Image Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

Opportunity was originally only guaranteed to last 90 days on the Red Planet. Upon landing on 25 January, 2004, its airbag-protected body rolled into a small crater in the equatorial region of Meridiani Planum. Before even leaving the crater, Opportunity found evidence of past water inside of it—including the presence of hematite "blueberries", rocks that only form in the presence of the liquid.

The runabout was one of a pair of Mars Exploration Rovers sent to explore the planet, and both lasted well past their expiry dates. Twin Spirit became stranded in a sand dune and sent its last transmission to Earth on 22 March, 2010. Opportunity carries on and despite the memory problems, has made several long drives in recent weeks as it trundles towards "Marathon Valley"—a spot so named because it will have reached a marathon's worth of driving when it gets there.

But science has been slowed in recent months by these memory issues. JPL (where rover operations are based) attempted a reset of Opportunity's flash memory in September following frequent resets. But problems continued through the rest of 2014. After another reset attempt in December, controllers elected to temporarily stop using Flash memory altogether.


Opportunity's approach to Cape Tribulation was captured in this Martian panorama on 5 January, 2015. Image Credit: NASA/JPL-Caltech

Driving with RAM memory, Opportunity reached the summit of Cape Tribulation early in 2015. It's the highest point that Opportunity has explored since 2011 as it roams the rim of Endeavour Crater. Tribulation is roughly 440 ft (135 metres) above the Martian plain below.

Part of the panorama includes a view of the United States flag that Opportunity carried to Mars, which is a tribute to the victims of the terrorist attacks on the World Trade Center in New York on 11 September, 2001. The flag is printed on a cable guard made of aluminum recovered from the site, and is also a nod to the workers at Honeybee Robotics who were creating the rover's rock abrasion tool at a site less than one mile from the WTC.

Our main image was processed and coloured by UK Mars enthusiast and blogger Stuart Atkinson. He writes: "What I try to create with my images is a vision of Mars, something that puts across—hopefully—the beauty of the planet and its landscapes. So my images are not photo-realistic, and I don’t claim them to be, but they are, I hope, one person’s depiction of Mars which reflect the planet’s incredible raw beauty and nobility."

As of 13 January, Opportunity's odometer is at 25.86 miles (41.62 kilometres).