mardi 24 mars 2015

NASA Reformats Memory of Longest-Running Mars Rover











NASA - Mars Exploration Rover B (MER-B) "Opportunity" patch.

March 24, 2015

Fast Facts:

- The rover team reformatted the aging rover's flash memory to restore use of overnight data storage

- Opportunity completed inspections of blocky rocks above Marathon Valley

- The rover is nearing the equivalent of a marathon in total driving distance

After avoiding use of the rover's flash memory for three months, the team operating NASA's 11-year-old Mars Exploration Rover Opportunity has reformatted the vehicle's flash memory banks and resumed storing some data overnight for transmitting later.

Mars 'Marathon Valley' Overlook

Image above: This view from NASA's Opportunity Mars rover shows part of "Marathon Valley," a destination on the western rim of Endeavour Crater, as seen from an overlook north of the valley. Image Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

The team received confirmation from Mars on March 20 that the reformatting completed successfully. The rover switched to updated software earlier this month that will avoid using one of the seven banks of onboard flash memory. Some of the flash-memory problems that prompted the team to adopt a no-flash mode of operations in late 2014 were traced to Bank 7. The remaining six banks provide more nonvolatile memory capacity than the rover has used on all but a few days since landing on Mars in January 2004.

Mars 'Marathon Valley' Overlook (False Color)

Image above: This view from NASA's Opportunity Mars rover shows part of "Marathon Valley" as seen from an overlook north of the valley. It was taken by the rover's Pancam on March 13, 2015. Image Credit: NASA/JPL-Caltech/Cornell Univ./Arizona State Univ.

In the no-flash mode of operations, Opportunity continued conducting science investigations and driving, but transmitted each day's accumulated data before powering down for overnight conservation of energy. Flash memory is nonvolatile, meaning it retains data even without power. Opportunity also uses random access memory, which retains data only while power is on.

Last week, Opportunity completed examination of unusual rocks it found at an overlook to its "Marathon Valley" science destination. The rover is approaching an elongated crater called "Spirit of St. Louis" on the path to Marathon Valley. As of March 23, Opportunity has 47 yards (43 meters) remaining to drive before its odometry passes the distance of an Olympic marathon race.

Mars 'Marathon Valley' Overlook, in Stereo

Image above: This stereo scene from NASA's Opportunity Mars rover shows part of "Marathon Valley" as seen from an overlook north of the valley on March 13, 2015.

"Opportunity can work productively without use of flash memory, as we have shown for the past three months, but with flash we have more flexibility for operations," said Opportunity Project Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena, California. "The rover can collect more data than can be returned to Earth on any one day. The flash memory allows data from intensive science activities to be returned over several days."

Rover's Progress Toward Mars Marathon, Sol 3966

Image above: This map updates progress that NASA's Mars Exploration Rover Opportunity is making toward reaching a driving distance equivalent to a marathon footrace. Image Credit: NASA/JPL-Caltech/Univ. of Arizona.

Marathon Valley was selected as a science destination because spectrometer observations from orbit indicate exposures of clay minerals. Before entering the valley, Opportunity will observe Spirit of St. Louis Crater, which holds an interior rock structure rising higher than the crater rim.

Mars Exploration Rover B (MER-B) "Opportunity". Image Credits: NASA/JPL-Caltech

As of March 16, Opportunity has driven 26.192 miles (42.152 kilometers) since it landed on Mars in January 2004. A marathon is 26.219 miles (42.195 kilometers).


Image above: This illustration depicts some highlights along the route as NASA's Mars Exploration Rover Opportunity drove as far as a marathon race during the first 11 years and two months after its January 2004 landing in Eagle Crater. The vehicle surpassed marathon distance of 26.219 miles (42.195 kilometers) with a drive completed on March 24, 2015, during the 3,968th Martian day, or sol, of Opportunity's work on Mars. For this map, north is on the left. Image Credit: NASA/JPL-Caltech/Cornell Univ./USGS/Arizona State Univ.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover Project for NASA's Science Mission Directorate in Washington. For more information about Spirit and Opportunity, visit: http://www.nasa.gov/rovers and http://marsrovers.jpl.nasa.gov

You can follow the project on Twitter and on Facebook at: http://twitter.com/MarsRovers and http://www.facebook.com/mars.rovers

Images (mentioned), Text, Credits: NASA/JPL/Guy Webster.

Best regards, Orbiter.ch

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