Mars Lives.

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http://marsrovers.jpl.nasa.gov/mission/status.html#opportunity

OPPORTUNITY UPDATE:  Helpful Wind Cleans Solar Panels - sols 3603-3609, Mar. 13, 2014-Mar. 19, 2014:

Opportunity is exploring 'Murray Ridge' on Solander Point, part of the rim of Endeavour Crater.

The rover continues to investigate the region called 'Cook Haven.' On Sol 3603 (March 13, 2014), Opportunity completed the in-situ (contact) analysis of a target called 'Augustine' with a Microscopic Imager (MI) mosaic and a placement of the Alpha Particle X-ray Spectrometer (APXS) on the same. On the next two Sols, the rover conducted remote sensing with the collection of Navigation Camera (Navcam) and Panoramic Camera (Pancam) images and a measurement of atmospheric argon with the APXS. Atmospheric opacity (tau) measurements using the Navcam were performed in support of the InSIght mission. On Sol 3607 (March 17, 2014) a short bump was planned to approach a target rock, called 'Sugarloaf.' However, the drive stopped after just 2.3 meters (7.55 feet) due to the rover sensing higher average current in three of the rover wheels. This was a safety check to detect possible embedding events. Although the rover did experience as much as 50% slip, there was no risk of embedding, just a steep upward climb. Given the difficult terrain, the approach to Sugarloaf would require multiple additional drives to be able to use the robotic arm on the rock surface. So, the science team chose to document Sugarloaf with more color imagery and to drive further south and west to new targets. On Sol 3609 (March 19, 2014), Opportunity drove about 16.35 meters (53.64 feet) to the southwest. The rover experienced a solar panel dust cleaning event between Sols 3605 and 3606 (March 15 and March 16, 2014). This resulted in about a 10% improvement in power production.
As of Sol 3609, the solar array energy production was 574 watt-hours with an atmospheric opacity (Tau) of 0.450 and an improved solar array dust factor of 0.777.

Total odometry is 24.10 miles (38.79 kilometers)

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http://www.youtube.com/v/xngUpUyyT70

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Opportunity keeps on Truckin... 

http://marsrovers.jpl.nasa.gov/mission/status.html#opportunity

OPPORTUNITY UPDATE:  Rover Has Enough Energy for Some Late-Night Work - sols 3697-3703, June 18, 2014-June 24, 2014:

Opportunity is exploring the west rim of Endeavour Crater. The rover is continuing south along the ridgeline that forms the spine of the crater rim, collecting color imagery of targets and outcrops along the way.

With ample energy, Opportunity has been able to conduct some late-night activities. On Sol 3697 (June 18, 2014), the rover collected an atmospheric argon measurement with the Alpha Particle X-ray Spectrometer (APXS), and took advantage of a Phobos moon imaging opportunity. On Sol 3698 (June 19, 2014), the rover proceeded just over 82 feet (25 meters) to the south with another Phobos imagining opportunity that night, and an argon measurement on the next night. Sol 3700 (June 21, 2014), was the first sol of a 2-sol 'touch 'n go' with the collection of a Microscopic Imager (MI) mosaic and subsequent APXS measurement on a surface target of opportunity. The rover then drove on the next sol, heading 42 feet (13.5) meters south.

On Sol 3703 (June 24, 2014), Opportunity began an approach to a surface target with a 31 feet (9.4-meter) move. Also, the project continues with the spacecraft clock correction, moving the clock about 3 seconds back each sol. There have been no Flash-related anomalies and the rover continues in good health.

As of Sol 3703 (June 24, 2014), the solar array energy production was 743 watt-hours with an atmospheric opacity (Tau) of 0.652 and a solar array dust factor of 0.894.

Total odometry is 24.60 miles (39.59 kilometers).

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Opportunity is having memory issues... 

OPPORTUNITY UPDATE:  Flash-Memory Reformat Planned  - sols 3759-3766, August 21, 2014-August 28, 2014:

Opportunity is on the west rim of Endeavour Crater heading toward 'Marathon Valley', a putative location for abundant clay minerals. However, flash-memory induced resets have increased in occurrence, preventing meaningful science until this problem can be corrected. The project is developing plans to reformat the flash file system to correct the problem.

A flash-memory reformat was done successfully five years ago on Spirit, but this will be the first time on Opportunity. The project is preparing the rover for the reformatting. With no master sequence running, the flash memory is being systematically emptied of science data products. On Sol 3762 (Aug. 24, 2014), the project activated a new communication table on the rover, insuring predictable communication for the next several weeks. Due to the complexity of the frequent resets hitting during high-gain antenna passes causing subsequent X-band faults, the team sent a real-time command of a special sequence that converts the next several X-band passes to use the low-gain antenna. This was completed on Sol 3766 (Aug. 26, 2014).

The next step in the plan is to boot the rover into a mode that does not use the flash file system. This will allow confirmation of the health of the rover independent of the flash file system. Also, the operations team has sequenced a checksum test of the lower portion of flash to get some data on the physical heath of the flash memory chips in general. Remaining science data will be returned from the flash file system prior to the reformat.

The rover remains power positive with a healthy energy balance, thermally stable and communicative both over X-band with the DSN and via UHF relay with the orbiters.

As of Sol 3764 (Aug. 26, 2014), the solar array energy production was 680 watt-hours with an estimated atmospheric opacity (Tau) of 0.858 and a solar array dust factor of 0.753.

Total odometry as of Sol 3765 (Aug. 27, 2014) is 25.28 miles (40.69 kilometers).

http://mars.jpl.nasa.gov/mer/mission/status.html#opportunity

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http://www.popsci.com/article/technology/opportunity-rovers-memory-undergo-reformat?dom=PSC&loc=recent&lnk=9&con=opportunity-rovers-memory-to-undergo-reformat

Opportunity Rover's Memory To Undergo Reformat
In preparation for another two years' work.

By Francie Diep
Posted 09.02.2014 at 1:00 pm 

Nearly a decade after it landed on Mars, NASA's Opportunity rover is about to get a fresh start. Opportunity's engineers plan to reformat its flash memory, which is good news, as the rover's mission has been renewed for another two years, Nature News reports.

Over their lifetimes, Opportunity and the now-dead Spirit rover provided crucial evidence that Mars once held persistent, neutral liquid water. Now, Opportunity's engineers are hoping the rover will make it to a site called Marathon Valley, where astronomers think there are several layers of exposed clay minerals that Opportunity could examine. The clay-ey site's name is a nod to Opportunity's journey, as the rover will have driven a marathon's distance by the time it gets to the valley. Opportunity already holds the record for the longest distance ever driven by wheels on a surface not on Earth.

Engineers have to perform some fixes, however, to ensure Opportunity's instruments will be ready for Marathon Valley. Over the past few months, the rover's computer has been resetting itself, interrupting its master sequence -- the machine's daily to-do list from its masters on Earth. The resets slow down Opportunity's data-gathering. NASA engineers think that Opportunity's flash memory has some worn-out cells, and a reformat will help them identify which cells to avoid in the future.

Engineers previously reformatted the flash memory on Spirit, but this will be the first time they've tried to reformat anything on Opportunity. Whether or not the reformatting works, the rover has proved incredibly long-lasting; its original goals were to survive three months on Mars and to drive only 0.62 miles.

[spuwho]

Per Aviation Week:

http://aviationweek.com/space/two-orbiters-one-comet-arriving-mars-soon

Two Orbiters, One Comet Arriving At Mars Soon



Scientists and spacecraft controllers in Denver, Bangalore and many points in between are preparing for a rush of activity at the planet Mars, where two new spacecraft designed to study its atmosphere will arrive later this month, followed shortly thereafter by a rare Oort Cloud comet.

If all goes as planned, the two orbiters and the comet Siding Spring should add volumes to human knowledge about where most of the red planet's water went, and perhaps about how it got there in the beginning.

NASA's only Mars mission in the current launch window—the $671 million Mars Atmosphere and Volatile Evolution (Maven)—is expressly designed to investigate whether the water that once ran on the surface escaped into space. India's Mangalyaan Mars Orbiter Mission (MOM)—its first flight to the red planet—can address some of the same questions (see page 42).

And Siding Spring's flyby of Mars will be the equivalent of a free trip to the Oort Cloud, the mysterious realm of icy planetesimals 5 trillion miles from the Sun, which might have showered the inner Solar System with primordial water and perhaps even the building blocks of life.

Mars being Mars, there is also a risk of spacecraft failure, compounded by the danger posed by high-speed comet debris. At 34 mi./sec.—the closing speed as Siding Spring crosses the orbit of Mars—even a dust mote could damage or destroy a delicate instrument or critical piece of spacecraft hardware. So Maven and MOM will interrupt their planned checkout periods to hunker down as the comet passes only 80,000 mi. from the planet they, hopefully, will be orbiting.

Recent ground observations of Siding Spring's path and coma suggest the comet will not pose as big a threat as originally feared, and mission scientists on all of the spacecraft at Mars are planning to take maximum advantage of the opportunity for observation that it represents (see page 42). But the guiding principle of spacecraft operation remains "safety first," particularly after the programs have spent 10 months and plenty of money getting to their objective.

"Safety and health of the spacecraft and instruments absolutely come first," says Bruce Jakosky, a planetary scientist at the University of Colorado's Laboratory for Atmospheric and Space Physics (LASP) who is the Maven principal investigator. "There is no question about that. So if there is something that happens in the run-up to the comet, we're going to make sure we're safe. We want to survive and do our mission."

Siding Spring will pass closest to Mars on Oct. 19. Maven will arrive there on Sept. 21, followed by MOM on Sept. 24. For Jakosky, who has managed the Scout-class mission from the beginning, the first order of business will be ensuring his spacecraft gets safely into orbit. Maven controllers have been in a 60-day "command moratorium" since the end of July that was designed into the Mars orbit-insertion (MOI) sequence to circumvent any action that might go wrong and cause problems.

"We just finished our last operational readiness test for orbit insertion," he said Aug. 11. "It's basically a rehearsal, and the team went through everything we're going to be doing on MOI day to make sure we knew the procedures, knew what we had to do and were prepared. So we're doing everything we can to be ready to ensure a success."

With a 12.5-min. one-way speed-of-light delay in radio signals between the Maven spacecraft and its controllers at the Lockheed Martin facility near Denver, where it was built, the actual MOI will be completely autonomous.

Nominally, the MOI is a three-day sequence leading up to a 34-min. burn beginning a little before 10 p.m. EDT on the 21st—a Sunday—that will slow the spacecraft enough to enter orbit. But there is plenty of redundancy built into the flight-computer programming in case something goes wrong.

"If it goes correctly we go into orbit; if it doesn't, we don't," says Jakosky. "In order to ensure it goes correctly, we have engine-out capability, so that if we lose one of the six thrusters we're using, we can still get into orbit on five of them. We also have a computer-reboot capability, so if something happens during the burn, we designed it so that we could have a 13.5-min. outage, and that's enough time for the computer to reboot, decide it still has a problem, swap sides, realize it's supposed to be in the middle of its burn, reacquire attitude, resume the burn and get into orbit."

Maven navigators are working with NASA's Deep Space Network to track the spacecraft very precisely, and may decide to conduct one more trajectory correction maneuver (TCM) nine days before MOI. Jakosky says a course-correction burn planned for the end of July was canceled because it was not needed. The aim-point is a 100-by-200-km box in the sky, and so far Maven is inside the box if not headed straight for the bull's-eye.

"Whether we do [the final TCM] will depend on what the tracking shows our trajectory to be, relative to our target point," he says.

Discovered just last year, the comet Siding Spring will swing past Mars Oct. 19, offering scientists an unprecedented close-up look at an Oort/Cloud object.
Mindful of the September 1999 loss of the Mars Climate Orbiter, the Maven MOI sequence also has provisions for an emergency orbit-raising maneuver at 24 hr. and then again at
6 hr. before insertion. The earlier spacecraft plunged too deeply into the atmosphere on arrival at the planet and disintegrated because of a mix-up between English and metric units of measurement (AW&ST Oct. 4, 1999, p. 40).

"The hooks are in there so we can do it if we need it," Jakosky says. "We don't expect to need it."

Five orbital-adjustment maneuvers are planned to put Maven into its 6,200 X 150-km (3,850 X 93-mi.) science orbit. Instrument checkout will run until the end of October, when the spacecraft is scheduled to begin a year-long data-collection session designed to help scientists understand the interactions between the upper Martian atmosphere, the solar wind and other elements of the space environment.

A primary objective is to test the theory that the liquid water that once flowed on the planet's surface was lost when the solar wind and ultraviolet radiation in sunlight stripped away the heavy, wet primordial atmosphere.

The instrument suite designed for the job consists of the Solar Wind Electron Analyzer (SWEA) to measure solar winds and electrons in the Martian ionosphere; the Solar Wind Ion Analyzer (SWIA), to measure solar wind and ion density and velocity in the planet's magnetosheath; the Suprathermal and Thermal Ion Composition (Static) instrument, which will measure ions in the atmosphere of Mars, including moderate energy escaping ions; and the Solar Energetic Particle (SEP) instrument to measure the impact of the solar wind on the planet's upper atmosphere.

Also on board are the Langmuir Probe and Waves (LPW) instrument, which includes an extreme ultraviolet sensor, to measure properties of the ionosphere, wave-heating in the upper atmosphere and extreme ultraviolet inputs into the atmosphere from the Sun. Rounding out the package is a magnetometer, which will measure interplanetary solar wind and magnetic fields in the ionosphere; a Neutral Gas and Ion Mass Spectrometer to measure the composition and isotopes of ions and thermal neutrals in the atmosphere; and an Imaging Ultraviolet Spectrograph for global remote sensing of the upper atmosphere and ionosphere at Mars.

Maven scientists designed the instruments to work across the entire range of the spacecraft's elliptical orbit, making in-situ measurements of the upper atmosphere at the lowest altitudes and then backing off for remote-sensing measurements that will allow researchers to extrapolate the low-altitude data out to global processes.

The arrival of a comet from the distant Oort Cloud, on a multimillion-year orbit that will reach its closest approach to the Sun five days after it passes Mars, is pure serendipity for comet experts. While the Maven team plans to switch off instruments that could be damaged if they are hit with debris while they are active, and to turn the spacecraft into the orientation that affords the greatest protection from any oncoming dust from Siding Spring, controllers also will interrupt instrument checkout and calibration to make observations of the event.

Still, safety comes first so at the point of greatest danger from the comet, plans call for Maven—and the other orbiters circling Mars that day—to be on the other side of the planet. Once its early orbital parameters are established, Jakosky says, controllers will adjust the orbit to minimize the danger by using Mars as a shield.

"We can get about 20 min. of hiding behind the planet, and the time of peak risk of the dust is thought to be between 30 and 60 min., so that is a significant risk reduction right there," he says.

Jakosky's counterparts at the Indian Space Research Organization are facing the same problems, and are considering the steps they can take to prepare the MOM spacecraft for the encounter. They are also working with Jakosky and his colleagues on possibly coordinating some scientific observations while the two orbiters are measuring the upper atmosphere.

"We're going to meet with some of the Indian investigators before our science mission starts to talk about what's possible," Jakosky says. "There is a strong desire to collaborate, and I don't know where it's going to head."

Of particular interest to the Maven scientists are the Lyman-alpha photometer and mass spectrometer on MOM. Maven, too, carries a mass spectrometer to measure chemical composition and coordinated observations at the same time from different locations which "allow you to separate out temporal and spatial variability," Jakosky says.

However, because the Maven and MOM teams are just beginning detailed discussions, the most likely outcome will be joint data analysis at the end of the science missions, he says. Maven scientists have also been working with scientists on the European Space Agency's Mars Express mission, which carries several instruments that can complement the Maven suite, so coordinated observations with that team are more likely. Joint data analysis with the Europeans is also in the cards, Jakosky says.

With the five-day delay in commissioning caused by the comet encounter, Maven probably will not be able to start its science mission until the second week in November. Jakosky says the annual American Geophysical Union meeting Dec. 15-19 in San Francisco is well timed for release of data on the comet encounter two months earlier.

"We think it is going to take about three months for us to come out with real, preliminary results about what Maven is telling us about Mars," Jakosky says of the primary mission objectives. "Before that, we're going to do everything we can to get data out and show people the types of things we're measuring; but in terms of grand pronouncements of what it all means, at least [for the] preliminary pronouncements, we're thinking about mid-to-late winter."

[BridgeTroll]

The reformat was successful... Opportunity Lives! 

OPPORTUNITY UPDATE:  Flash-Memory Reformat Successful!  - sols 3773-3778, September 04, 2014-September 09, 2014:

Opportunity is on the west rim of Endeavour Crater heading towards 'Marathon Valley,' a putative location for abundant clay minerals.

The rover's Flash file system was successfully reformatted on Sol 3773 (Sept. 4, 2014). The Flash space available is slightly smaller (<1%) than before the reformat, consistent with the reformatting process flagging some bad cells to avoid. On Sol 3775 (Sept. 6, 2014), some scripts and configuration files were copied back to Flash from EEPROM (other non-volatile storage) were they were kept during the reformat. Other configuration files were loaded from the ground on Sol 3776 (Sept. 7, 2014). The rover has performed without any anomalies or unusual behavior since the reformat.

A drive was sequenced on Sol 3778 (Sept. 9, 2014), using visual odometry to navigate around potential rock obstacles. The drive stopped almost as soon as it started because the rover's visual odometry could not find enough visual features for the algorithm to converge. The plan ahead is to re-sequence the drive but to instruct the rover to use a different scene with more visual features for the visual odometry.

As of Sol 3778 (Sept. 9, 2014), the solar array energy production was 694 watt-hours with an atmospheric opacity (Tau) of 0.879 and a solar array dust factor of 0.754.

Total odometry is 25.28 miles (40.69 kilometers).

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OPPORTUNITY UPDATE:  Opportunity's Heading to a Small Crater Called 'Ulysses'  - sols 3786-3792, September 17, 2014-September 23, 2014:

Opportunity is on the west rim of Endeavour Crater heading towards "Marathon Valley," a putative location for abundant clay minerals.

The rover is headed to a near-term target, a small crater named "Ulysses." The rover is moving closer to Ulysses to get a peek inside. On Sol 3787 (Sept. 18, 2014), Opportunity drove a little over 44 feet (13.5 meters) in rocky terrain, requiring the use of Visual Odometry to safely navigate. On Sol 3789 (Sept. 20, 2014), the rover moved closer to the rim of Ulysses, but the drive stopped after 15 feet (4.6 meters) because Visual Odometry was not tracking on the last steps. An evening Alpha Particle X-ray Spectrometer measurement of atmospheric argon was performed on Sol 3790 (Sept. 21, 2014). The rover continued closer to Ulysses on the next sol with a 13-feet (4-meter) bump. High slip prevented the rover from completing the turn for communication at the end of the drive.

Recently, there were more Flash-related events. Two more "amnesia" events occurred on the evenings of Sols 3786 and 3789 (Sept. 17 and Sept. 20, 2014). And two Flash write errors to Bank 7 occurred on Sols 3791 and 3792 (Sept. 22 and Sept. 23, 2014). All these events were benign and did not impact the rover's operation. The project continues to investigate. Otherwise, Opportunity continues in good health.

As of Sol 3792 (Sept. 23, 2014), the solar array energy production was 639 watt-hours with an atmospheric opacity (Tau) of 0.889 and a solar array dust factor of 0.740.

Total odometry is 25.34 (40.77 kilometers).

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OPPORTUNITY UPDATE:  Dust Levels Back to Normal  - sols 3827-3834, October 29, 2014-November 06, 2014:

Opportunity is on the west rim of Endeavour Crater heading towards 'Marathon Valley,' a putative location for abundant clay minerals about a mile (1.6 kilometers) to the south.

The rover has completed the investigation of the Ulysses crater and is exiting the ejecta field to resume the strategic drive south. The regional dust storms that had raised atmospheric opacity (tau) have abated and the tau is returning to normal seasonal levels. On Sols 3827 and 3828 (Oct. 29 and Oct. 30, 2014), Opportunity drove 38 feet (11.6 meters) and 39 feet (12.0 meters), respectively in rocky terrain to exit the Ulysses crater ejecta field.

On Sol 3829 (Oct. 31, 2014), the rover again drove to complete the exit from the ejecta field, but high slip terminated the drive after just 5 feet (1.5 meters). A careful assessment indicated the rover was safe and the cause of the slip was the high slopes and loose soil.

On Sol 3832 (Nov. 3, 2014), a modified drive of over 105 feet (32 meters) permitted the rover to safely exit the ejecta field. On Sols 3833 and 3834 (Nov. 4 and Nov. 6, 2014), Opportunity headed south with drives of 106 feet (32.4 metes) and 132 feet (40.25 meters) respectively. The project has also implemented a more advanced diagnostic for amnesia events, if any occur. The rover continues in good health.

As of Sol 3834 (Nov. 6, 2014), the solar array energy production was 505 watt-hours with an improved atmospheric opacity (Tau) of 1.359 and a solar array dust factor of 0.711.

Total odometry is 25.45 miles (40.95 kilometers).

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Old age is beginning to affect memory... 

OPPORTUNITY UPDATE:  Flash-Memory Reformat Planned  - sols 3852-3861, November 24, 2014-December 03, 2014:

Opportunity is on the west rim of Endeavour Crater heading towards 'Marathon Valley,' a putative location for abundant clay minerals less than a mile (about a kilometer) to the south.

The rover is stopped at an interesting geologic unit and conducting in-situ (contact) measurements. On Sol 3853 (Nov. 25, 2014), the rover used the robotic arm to reposition the Alpha Particle X-ray Spectrometer (APXS) for a surface measurement. On the next sol, the Rock Abrasion Tool (RAT) was used to brush a new surface target, which was then imaged with the Microscopic Imager (MI) and examined with the APXS.

With the Thanksgiving holiday, a multi-sol plan was built to collect Pancam images over the long holiday weekend. However, the rover experienced amnesia events and then a computer reset around Sol 3856 (Nov. 28, 2014). After the reboot, the rover was no longer under sequence control and was unable to mount the flash (non-volatile) memory. The project restored the rover to normal sequence operation on Sol 3859 (Dec. 1, 2014), but the flash file system remained unavailable. The project prepared for a reformatting of the flash memory on Sol 3862 (Dec. 4, 2014).

As of Sol 3859 (Dec. 1, 2014), solar-array energy production was 468 watt-hours, with an atmospheric opacity (Tau) of 1.376 and a solar-array dust factor of 0.638.

Total odometry as of Sol 3861 (Dec. 3, 2014) is 25.66 miles (41.30 kilometers).

[BridgeTroll]

Getting worse...

OPPORTUNITY UPDATE:  Flash-Memory Resets Continue  - sols 3862-3867, December 04, 2014-December 09, 2014:

Opportunity is on the west rim of Endeavour Crater heading towards 'Marathon Valley,' a putative location for abundant clay minerals only about a mile (about 1 kilometer) to the south.

Because of the deteriorating performance of the Flash file system, the project reformatted the rover's Flash memory on Sol 3862 (Dec. 4, 2014). Although the rover's operation improved immediately after the reformat, Flash behavior quickly deteriorated. Opportunity experienced a set of resets on Sols 3864 and 3865 (Dec. 6 and Dec. 7, 2014). After this, the project made the decision to operate the rover without the use of Flash memory until another fix can be implemented. On Sol 3866 (Dec. 8, 2014), the rover was booted without using Flash (and instead storing data products in volatile RAM memory) and all the fault conditions were cleared. On Sol 3867 (Dec. 9, 2014), Opportunity performed light science activities in preparation for driving on the next sol. Longer term, the project is developing a strategy to mask off the troubled sector of Flash and resume using the remainder of the Flash file system.

As of Sol 3867 (Dec. 9, 2014), the solar array energy production was 500 watt-hours, an atmospheric opacity (Tau) of 1.215 and a solar array dust factor of 0.659.

Total odometry is 25.66 miles (41.30) kilometers.

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http://mars.jpl.nasa.gov/mer/newsroom/pressreleases/20141211a.html

December 11, 2014


MARS EXPLORATION ROVER MISSION STATUS REPORT
Opportunity Working in No-Flash Mode for Now




NASA's Mars Exploration Rover Opportunity is continuing its traverse southward on the western rim of Endeavour Crater during the fall of 2014, stopping to investigate targets of scientific interest along way. This view is from Opportunity's front hazard avoidance camera on Nov. 26, 2014.

Persistent computer resets and "amnesia" events on NASA's Mars Exploration rover Opportunity that have occurred after reformatting the robot's flash memory have prompted a shift to a working mode that avoids use of the flash data-storage system.

The most recent reformatting of Opportunity's flash memory was last week. Following that, performance of the flash memory remained intermittent, and difficulty in placing data into the memory led to computer resets during the weekend.

Flash memory retains information even when power is shut off during the rover's overnight power-conserving "sleep" time. In the no-flash mode, the rover can continue normal operations of science observations and driving, though it cannot store data during the overnight sleep. Data gathered each Martian day is stored in volatile memory, which on Opportunity is random-access memory, or RAM. That data stored in volatile memory is relayed Earthward before sleep because it is lost when power goes off.

The team is developing a set of commands to restore usability of the flash memory through an overhaul more extensive than the reformatting that has been used so far. The incidents of Opportunity's flash memory not accepting data for storage have occurred in only one of the seven banks of flash microchip circuitry on board. The team plans to send commands for the rover to avoid that entire bank.

"The mission can continue without storing data to flash memory, and instead store data in volatile RAM," said Mars Exploration Rover Project Manager John Callas or NASA's Jet Propulsion Laboratory, Pasadena, California. "While we're operating Opportunity in that mode, we are also working on an approach to make the flash memory usable again. We will be sure to give this approach exhaustive reviews before implementing those changes on the rover."

Opportunity is examining outcrops on the western rim of Endeavour Crater while traversing southward toward "Marathon Valley," where clay minerals have been detected in observations by NASA's Mars Reconnaissance Orbiter.

NASA's Mars Exploration Rover Project landed twin rovers Spirit and Opportunity on Mars in early 2004 to begin missions planned to last only three months. Both rovers far exceeded those original plans. Spirit worked for six years, and Opportunity is still active. Findings about ancient wet environments on Mars have come from both rovers. The 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.

[BridgeTroll]

http://phys.org/news/2015-02-mars-rover-nearing-marathon.html

The map shows the rover's location as of Feb. 10, 2015, in the context of where it has been since late December 2014 and the "Marathon Valley" science destination ahead. Opportunity is within about 220 yards (200 meters) of completing a marathon. The green band indicates where it could reach the official Olympic marathon-race distance of 26.219 miles (42.195 kilometers). The rover's route might zigzag as the rover team chooses a path toward Marathon Valley, so there is uncertainty about where exactly it will pass marathon distance. In this image, north is up. The southern end of the solid blue line indicates the rover's position after a drive on Sol 3926, the 3,926th Martian day of Opportunity's work on Mars (Feb. 9, 2015). The rover team plans to drive Opportunity near or into "Spirit of St. Louis Crater" before the rover enters Marathon Valley. This area is all part of the western rim of Endeavour Crater. Credit: NASA/JPL-Caltech/Univ. of Arizona

Read more at: http://phys.org/news/2015-02-mars-rover-nearing-marathon.html#jCp

NASA's Mars Exploration Rover Opportunity is nearing a location on Mars at which its driving distance will surpass the length of a marathon race.

A drive on Feb. 8, 2015, put the rover within 220 yards (200 meters) of this marathon accomplishment. An Olympic marathon is 26.219 miles (42.195 kilometers).

Opportunity is headed for a portion of the western rim of Endeavour Crater where observations by NASA's Mars Reconnaissance Orbiter have detected multiple types of clay minerals. These minerals are indicative of an ancient wet environment where water was more neutral rather than harshly acidic. More than six months ago, the rover team informally named that destination "Marathon Valley," having estimated what the odometry would total by the time Opportunity gets there.

"When Opportunity was in its prime mission 11 years ago, no one imagined this vehicle surviving a Martian winter, let alone completing a marathon on Mars," said Mars Exploration Rover Project Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena, California. "Now, that achievement is within reach as Opportunity approaches a strategic science destination. What's most important about the longevity and driving distance the mission keeps extending are not numerical thresholds, but the wealth of scientific information returned about Mars, made possible by these feats."

Before driving Opportunity into Marathon Valley, the team plans to use the rover for observations of an impact crater called "Spirit of Saint Louis Crater," at the entrance to the valley.

The team is operating Opportunity in a mode that avoids use of the rover's flash memory. In this mode, data gathered during each Martian day are stored in volatile memory and transmitted to an orbiter before the rover's overnight, energy-conserving "sleep." NASA orbiters Mars Odyssey and Mars Reconnaissance Orbiter relay the rover data to Earth.

Opportunity engineers plan in coming weeks to upload a software revision they have developed to enable resuming use of non-volatile flash memory. It is designed to restore Opportunity's capability to store data overnight or longer, for transmitting later.

During its original three-month prime mission, beginning after landing on Jan. 25, 2004, UST (Jan. 24, 2004, PST) Opportunity drove 0.48 mile (771.5 meters). Its twin, NASA's Mars Exploration Rover Spirit, landed three weeks earlier and covered 0.39 mile (635 meters) in its three-month prime mission. Both Spirit and Opportunity have returned compelling evidence about wet environments on ancient Mars. Spirit's mission ended in 2010. Since 2011, Opportunity has been investigating the western rim of Endeavour, a crater that is 14 miles (22 kilometers) in diameter.

The rover climbed to its highest elevation on the Endeavour rim on Jan. 6, 2015, reaching a point about 440 feet (135 meters) above the local plains. It has driven about 440 yards (400 meters) since then, mainly southward toward the entrance to Marathon Valley.


Read more at: http://phys.org/news/2015-02-mars-rover-nearing-marathon.html#jCp

[Jason]

I think the Martians are helping it along.....