Scientist Thrilled to See Layers in Mars Rocks Near Opportunity

MEDIA RELATIONS OFFICE JET PROPULSION LABORATORY CALIFORNIA INSTITUTE OF TECHNOLOGY NATIONAL AERONAUTICS AND SPACE ADMINISTRATION PASADENA, CALIF. 91109. TELEPHONE (818) 354-5011

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Guy Webster (818) 354-5011 Jet Propulsion Laboratory, Pasadena, Calif.

Donald Savage (202) 358-1547 NASA Headquarters, Washington, D.C.

NEWS RELEASE: 2004-039 January 27, 2004

Scientist Thrilled to See Layers in Mars Rocks Near Opportunity

New pictures from NASA's Mars Exploration Rover Opportunity reveal thin layers in rocks just a stone's throw from the lander platform where the rover temporarily sits.

Geologists said that the layers -- some no thicker than a finger -- indicate the rocks likely originated either from sediments carried by water or wind, or from falling volcanic ash. "We should be able to distinguish between those two hypotheses," said Dr. Andrew Knoll of Harvard University, Cambridge, a member of the science team for Opportunity and its twin, Spirit. If the rocks are sedimentary, water is a more likely source than wind, he said.

The prime goal for both rovers is to explore their landing areas for clues in the rocks and soil about whether those areas ever had watery environments that could possibly have sustained life.

Controllers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., plan to tell Opportunity tonight to start standing up from the crouched and folded posture in which it traveled to Mars.

"We're going to lift the entire rover, then the front wheels will be turned out," said Mission Manager Jim Erickson of JPL. Several more days of activities are still ahead before the rover will be ready to drive off the lander.

"We're about to embark on what could be the coolest geological field trip in history," said Dr. Steve Sqyures of Cornell University, Ithaca, N.Y., principal investigator for the rovers' science payload.

The layered rocks are in a bedrock outcrop about 30 to 45 centimeters (12 to 18 inches) tall, and only about eight meters (26 feet) away from where Opportunity came to rest after bouncing to a landing three days ago. Examination of their texture and composition with the cameras and spectrometers on the rover may soon reveal whether they are sedimentary, Knoll predicted.

Scientists also hope to determine the relationship between those light-colored rocks and the dark soil that covers most of the surrounding terrain. The soil may contain the mineral hematite, which was identified from orbit and motivated the choice of Opportunity's landing area, Squyres said.

Opportunity successfully used its high-gain antenna for the first time yesterday. The rover is losing some if its battery charge each night, apparently due to an electric heater at the shoulder joint of the rover's robotic arm. A thermostat turns on the heater whenever the air temperature falls to levels that Opportunity is experiencing every night. The heater is not really needed when the arm is not in use, but ground control has not been able to activate a switch designed to override the thermostat, Erickson said. Mission engineers are working to confirm the diagnosis, determine the ramifications of the power drain, and propose workarounds or fixes.

Meanwhile, engineers working on Spirit have determined that the high-gain antenna on that rover is likely in working order despite earlier indications of a possible problem. They are continuing to take information out of Spirit's flash memory. Results from a testbed simulator of the rover's electronics supported the diagnosis of a problem with management of the flash memory, reported JPL's Jennifer Trosper, mission manager.

JPL, a division of the California Institute of Technology in Pasadena, manages the Mars Exploration Rover project for NASA's Office of Space Science, Washington, D.C. Images and additional information about the project are available from JPL at

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and from Cornell University at

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Reply to
Ron
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I admit I haven't been following Spirit's condition very closely for a while. Is this flash memory mismanagement problem going to turn out to be failure due to rewriting the same cells too much? Maybe every time it started up in the morning, it hadn't saved the access pattern and wasn't distributing writes evenly?

Reply to
Garrett Mace

Latest theory is the flash memory have built up way to many files for the system to cope with. Many files can pressure main memory alot(managed by the OS perhaps..)

Reply to
Nils O. Selåsdal

Why haven't I heard even a single comment about whether Opportunity has the same latent problem and might likewise become debilitated? Seems to me there should be some real urgency in getting Spirit fixed if only to avoid the same problem with Opportunity when it should disembark the lander shell.

Has anyone read anything in any NASA release about this concern???

Jim

Reply to
Jim Hewitt

I would hope that the software for the two rovers was written by different contractors. Ideally the computer hardware would be different too. It's about the only way to avoid common-mode faults.

Bill Marshall

Reply to
Bill Marshall

Ughhhh. I hope NOT to both of those.

That's a sure-fire way to double the cost of the two missions.

Two sets of hardware test programs. Two sets of software development, testing, operating and debugging teams.

The idea of sending two as-close-as-possible identical rovers is to dramatically lower the cost of the missions.

I mean, did we send up a completely different LEM for every Apollo landing? Nope, it would have been a very bad idea.

Reply to
Alan Kilian

The software is essentially the same in both rovers. They did not take the Space Shuttle approach of having different contractors develop the flight software and the backup flight software (in fact they don't have a backup flight software load). The current suspicion that the problem in Spirit is due to an excessive amount of files in the FLASH memory has led them to begin deleting the unneeded cruise mode files from flash in both rovers. Once they conclusively determine the fault with Spirit (if they are able to), they will likely apply any applicable software fix to Opportunity as well.

Jerry

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-- Jerry Petrey

-- Senior Principal Systems Engineer - Navigation (GPS/INS), Guidance, & Control

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Reply to
Jerry Petrey

Hey I wasn't suggesting the whole rover should have been built by separate contractors! The principle of different software is quite widely used where safety is paramount. In this case, it is more an issue of getting a repairman to the site. I guess it comes down to how much you are prepared to risk mission failure. I rather suspect it was an almost total lack of redundant systems (for reasons of cost) that led to Beagle 2 disappearing without trace, and worse, they have no idea why so far.

Bill Marshall

Reply to
Bill Marshall

I have looked at this imagery using 3D devices,

I have not seen the fine scale layering yet.

Perhaps we get the data and then opine ?

LH

Reply to
Louis Hissink

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