[meteorite-list] Memory Reformat Planned for Opportunity Mars Rover

[Ron Baalke]

http://www.jpl.nasa.gov/news/news.php?release=2014-292

Memory Reformat Planned for Opportunity Mars Rover
Jet Propulsion Laboratory
August 29, 2014

Mars Exploration Rover Mission Status Report

An increasing frequency of computer resets on NASA's Mars Exploration 
Rover Opportunity has prompted the rover team to make plans to reformat 
the rover's flash memory.

The resets, including a dozen this month, interfere with the rover's planned 
science activities, even though recovery from each incident is completed 
within a day or two.

Flash memory retains data even when power is off. It is the type used 
for storing photos and songs on smart phones or digital cameras, among 
many other uses. Individual cells within a flash memory sector can wear 
out from repeated use. Reformatting clears the memory while identifying 
bad cells and flagging them to be avoided.

"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."

The project landed twin rovers Spirit and Opportunity on Mars in early 
2004 to begin missions planned to last only three months. Spirit worked 
for six years, and Opportunity is still active. Findings about ancient 
wet environments on Mars have come from both rovers.

The project reformatted the flash memory on Spirit five years ago to stop 
a series of amnesia events Spirit had been experiencing. The reformatting 
planned for early next month will be the first for Opportunity. Even after 
the rover has been active for more than a decade and is currently about 
125 million miles (about 200 million kilometers) from JPL, the rover team 
can still perform this type of upkeep.

Preparations include downloading to Earth all useful data remaining in 
the flash memory and switching the rover to an operating mode that does 
not use flash memory. Also, the team is restructuring the rover's communication 
sessions to use a slower data rate, which may add resilience in case of 
a reset during these preparations.

The Mars Exploration Rover Project is one element of NASA's ongoing and 
future Mars missions preparing for a human mission to the planet in the 
2030s. JPL, a division of the California Institute of Technology, manages 
the project for NASA's Science Mission Directorate in Washington.

For more information about NASA's Mars rovers Spirit and Opportunity, 
visit these sites:

http://www.nasa.gov/rovers

http://marsrovers.jpl.nasa.gov

Follow the project on Twitter at:

http://twitter.com/MarsRovers

On Facebook, visit:

http://www.facebook.com/mars.rovers

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster at jpl.nasa.gov

2014-292