by Cat Ellen, contributing writer

Computer memory housekeeping

Three month tour, ten years later and still working. The view from NASA's Mars rover Opportunity in August 2014. (Photo Credit: NASA/JPL-Caltech)

Three month tour, ten years later and still working. The view from NASA’s Mars rover Opportunity in August 2014. (Photo Credit: NASA/JPL-Caltech)

Ever been frustrated with a computer that just keeps rebooting? Software running slow or glitchy? Found it necessary to “wipe the cache” or (as many Windows users know) “reformat the drive” and start from scratch? These analogies might be slightly overkill, but even Martian rovers sometimes need the technician’s magic touch.

Computer resets have become increasingly frequent for NASA’s Mars Exploration Rover Opportunity (Oppy, to friends on Twitter). The science team here on Earth plans to reformat Oppy’s flash memory to address the problems.

For the uninitiated, flash memory maintains information on equipment even when powered off. In everyday use on earth, you rely on flash memory to store music and pictures on your cell phones and cameras. And just like when sections of your carpet wear out from always walking in the same space, sections of flash memory can wear out from repetition. Reformatting finds the worn out cells, marks them to be avoided, and clears everything out to start fresh again.

“Worn-out cells in the flash memory are the leading suspect in causing these resets,” said John Callas of NASA’s Jet Propulsion Laboratory, Pasadena, California, project manager for NASA’s Mars Exploration Rover Project. “The flash reformatting is a low-risk process, as critical sequences and flight software are stored elsewhere in other non-volatile memory on the rover.”

Opportunity landed on Mars with twin rover Spirit ten years ago, in early 2004. Spirit logged six years of scientific exploration and Opportunity remains active even though the original mission was only planned for three months. Talk about some amazing tech support: JPL’s rover team continues to work with Oppy from 125 million miles away. Go, team!

Science from up above

Digital Terrain Model (DTM) images of terraced craters on Mars (image credit: Ali Bramson)

Digital Terrain Model (DTM) images of terraced craters on Mars (image credit: Ali Bramson) 

Off the Mars surface, high overhead in the Martian skies, the Mars Reconnaissance Orbiter (MRO) delights researchers from many institutions, not just NASA. Over at the Department of Planetary Sciences at the University of Arizona, graduate student Ali Bramson studies ice under the surface of Mars. This week, she shared some of her observations in Martian Diaries blogs from MRO.

“Imagine if there was a layer of ice as tall as a 13-story building underneath the entire state of Texas. We have found a layer of ice that big under a region of Mars called Arcadia Planitia,” Bramson writes. “I am using impact crater measurements to learn more … [and] studying the radar signals that bounce off the ice and go back to the Mars Reconnaissance Orbiter (MRO) spacecraft’s SHARAD (Shallow Radar) instrument. The radar measurements are telling us about the composition of the ice.”

Layers of ice, rock and ice, or just rock react differently when impacted by meteors, asteroids, or other debris. Many of the impact craters on Mars appear to have terraced structures indicating layers with different compositions. Equipment on the Orbiter can take stereo images of these craters, allowing scientists to better measure the depths of the layers. These visual measurements are combined with radar measurements that bounce different through ice than off the surface of rock.

Want More?

  • Mars Exploration Program
  • Twitter: @MarsRovers, Spirit and Oppy
  • Twitter: @MarsCuriosity
  • Twitter: @NASAJPL
  • Facebook: NASA’s Curiosity Mars Rover
  • Mars Reconnaissance Orbiter

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