Well, let's hope for the best with both rovers..It would be a shame to lose both due to a dust storm..
However, that is a peril that was known when they were sent.
I 'd like to think they will be ok, but what was to be found at Victoria Crater? We might not know for a long time.

Shifting Sands on Mars

As dust storms darkened the Martian sky, driving down solar power levels, NASA's Mars Exploration Rover Spirit captured images of wind-blown material moving across the Martian surface. As on Earth, winds that loft dust into the atmosphere can also move materials on the ground.

While waiting for the dust to clear, Spirit captured images of small ripples of sand beneath the rover's robotic arm that moved slightly closer to the rover over a period of five sols (Martian days). The ripples moved a distance of 1 to 2 centimeters, or about an inch, driven by Martian winds between July 20 and July 25, 2007.

Image credit: NASA/JPL-Caltech

Source: NASA/JPL - Mars Exploration Rovers - Spirit

Mars Exploration Rover Status Report: Situation Improves; Spirit Resumes Using Robotic Arm

08.07.07

Slight clearing of still-dusty Martian skies has improved the energy situation for both Spirit and Opportunity, allowing controllers to increase the rovers' science observations.

Spirit is even being commanded to move its arm for the first time in nearly three weeks. It will position the arm's microscopic imager to take a series of photographs of two soil targets and one rock target. Opportunity's planned science observations are for studies of the atmosphere.


Image above: Spirit moved its robotic arm during the rover's 1,277th
Martian day (Aug. 6) for the first time in 20 days.
Image credit: NASA/JPL-Caltech/Cornell
+ Full image and caption

Energy production from solar arrays increased to 295 watt hours on Spirit's 1,276th Martian day, or sol, which ended early Aug. 6, and to 243 watt hours on Opportunity's sol 1,255 which ended midday Aug. 5. The solar panels generate electricity from sunlight. Dust storms obscuring the sun have cut daily output as low as 261 watt hours on Spirit and 128 watt hours on Opportunity in recent weeks, compared with levels above 700 watt hours per sol before the current series of Martian dust storms began in June. One hundred watt hours is what it takes to run a 100-watt bulb for one hour.

The increased output from the solar panels, though slight, has allowed Opportunity to fully charge its batteries and Spirit to bring its batteries to nearly full charge. Also, the temperature of the core electronics module on Opportunity, which was of concern when it fell to minus 35 degrees Fahrenheit (minus 37 Celsius) last week, has increased to minus 28.1 degrees Fahrenheit (minus 33.4 degrees Celsius).

"Conditions are still dangerous for both rovers and could get worse before things get better," said John Callas, rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

"We will continue our cautious approach to the weather and configure the rovers to maintain a high state of charge on the batteries. Communication sessions with both rovers will remain limited until the skies clear further."

Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278/5011

Source: NASA - Missions - Mars Rovers

this is sort of good news for our friends. I think they will come out of this and continue their tasks. Let's hope for the best. Thank you Waspie for the update,

I thought it would please you Bulldog. It is actually slightly better than you thought. When I copied the article I accidentally missed to replace the first two paragraphs from the previous with the new information. I have corrected that now.

The Rovers are not out of danger yet but this is encouraging news. I don't know enough about these Martian sandstorms to know what the probability is that they will worsen again. As I have said before, these rovers really most be getting close to the end of their lives but I will be mightily disappointed if Opportunity doesn't get the chance to show us the inside of Victoria Crater.

This is trully a remarkable achievement by the people at NASA. These rovers have simply lasted so much longer than anyone thought possible, they deserve vast amounts of publicity but sadly I don`t forsee that happening anytime soon. They seem to get a brief mention when they reach another milestone in terms of time spent on the planet but thats it. In my opinion completly unacceptable, but people would rather hear about celebrities than true scientific achievements. Here's hoping they can keep on going.

Well the fact of it is, they have made it this far Waspie, and that kind of makes them both infallable, in a sense.
I myself don't think they are at the end, something major would have to happen like a computer crashing, a battery croaking or complete immobility(burried in sand). Let's wait and see if they make it...I think they will, but on a limited basis until the dust gets blowed off the solar panels.
Maybe NASA should have included wipers and window washing fluid?

Update: Spirit and Opportunity

SPIRIT UPDATE: Spirit Tries to Coax Dust from Microscopic Imager
- sol 1288-1294, August 23, 2007:

For the first time since arriving on Mars in 2004, Spirit attempted to remove dust from the microscopic imager in a "blobs away" campaign to help the rover recover from a series of dust storms. The rover remained healthy as the Gusev Crater region continued to emerge from the recent storms. Gloominess caused by suspended dust in the atmosphere remained high but continued its downward trend. Dust falling out of the atmosphere continued to accumulate on the solar panels, limiting power gains from decreasing atmospheric opacity, known as Tau.

Between the rover's 1,288th and 1,291st Martian days, or sols, of exploration (Aug. 18 and Aug. 21, 2007), Tau values went down from 3.2 to 3.0. During the same time, the accumulation of dust on the solar arrays rose from 0.664 to 0.640 (a dust factor of 1.0 corresponds to a perfectly clean array). Solar energy on sol 1291 (Aug. 21, 2007) was 313 watt-hours (100 watt-hours is what it takes to light a 100-watt bulb for 1 hour).

The "blobs away" campaign, designed to dump dust from the surface of the microscopic imager lens, involved repeatedly taking images, opening and closing the dust cover, pointing the instrument slightly upward at an angle of 20 degrees (with the hinge down to avoid dumping caked dust on the lens), and taking more images and opening and closing the dust cover. Improved image quality after the procedure indicated that either some dust fell out or simply moved around. Dust decontamination efforts continue.

Spirit acquired microscopic images of mobile surface ripples and a soil target nicknamed "Norma Luker" on Sol 1291 (Aug. 21 2007). Despite dust motes on the lens, the images were useful to the science team.

Engineers were investigating the cause of a failed transmission on sol 1292 (Aug. 22, 2007), in which planned activities did not get on board the spacecraft. Potential causes being investigated included an uplink glitch or interference from a simultaneous uplink to the Mars Reconnaissance Orbiter.

Spirit "drove" 42 centimeters (16 ½ inches) to a new position. Weekend plans called for the first multi-meter drive toward the elevated plateau known as "Home Plate" as well as test transmissions to the European Mars Express orbiter in support of next year's arrival of the Phoenix spacecraft now en route to Mars.

Martian weather reports as of Aug. 22 indicated a lull in afternoon storm activity on the red planet, with no new storm activity visible within a few thousand kilometers of either Mars rover site. Skies remained dusty and were expected to continue to clear slowly.

Sol-by-sol summary:

In addition to daily direct-from-Earth uplinks over the rover's high-gain antenna, relays to Earth at UHF frequences via the Odyssey orbiter, surveys of the sky and ground with the miniature thermal emission spectrometer, measurements of atmospheric opacity with the panoramic and navigation cameras, and image acquisition with the front and rear hazard avoidance cameras, Spirit completed the following activities:

Sol 1288 (Aug. 18, 2007): Spirit studied Norma Luker with the alpha-particle X-ray spectrometer.

Sol 1289: Spirit monitored dust accumulation on the rover mast, collected data on the external calibration target with the miniature thermal emission spectrometer, and completed a survey at high sun with the panoramic camera.

Sol 1290: Spirit surveyed the horizon with the panoramic camera and performed dust ejection maneuvers with the microscopic imager.

Sol 1291: Spirit took thumbnail images of the sky with the panoramic camera, checked for drift (changes with time) in the miniature thermal emission spectrometer, and acquired stereo microscopic images of Norma Luker. The rover moved the microscopic imager and acquired stereo microscopic views of surface ripples, stowed the robotic arm, and acquired hazard avoidance camera images to document the stowing of the arm.

Sol 1292: Plans for a day of remote sensing and acquisition of full-color images of a target known as "Eileen Dean" failed to get on board.

Sol 1293: Spirit checked for drift in the miniature thermal emission spectrometer, acquired movie frames in search of dust devils using the navigation camera, and took full-color images using all 13 filters of the panoramic camera of a target known as "Gertrude Weise12." The rover acquired miniature thermal emission spectrometer data from the same target before rolling a short distance away. After the short drive, the rover took images of its new location with the navigation camera and hazard avoidance cameras.

Sol 1294 (Aug. 24, 2007): Plans called for Spirit to check for drift in the miniature thermal emission spectrometer, acquire movie frames in search of dust devils with the navigation camera, and survey the horizon with the panoramic camera.

Odometry:

As of sol 1293 (Aug. 23, 2007), Spirit's total odometry was 7,154 meters (4.45 miles).

Spirit Update Archive



OPPORTUNITY UPDATE: Brightening Skies Bolster Opportunity
- sol 1256-1265, Aug 23, 2007:

Opportunity is healthy and remains perched near the rim of "Victoria Crater." The rover was on a low-power schedule that alternated between a 3-sol plan and a 4-sol plan.

Tau (atmospheric opacity) has begun to stabilize this week at around 3.7, resulting in solar array energy between 230-240 watt hours. Therefore in the upcoming week, the team will return to nominal planning.

The rover conducted a lot of what engineers call "runout science." This includes: panoramic camera wide-range tau measurements, navigation camera tau measurements, navigation camera cloud measurements, panoramic camera soria (imaging a rough, rocky area near the rover), front hazard avoidance camera images, rear hazard avoidance camera images, navigation camera images, panoramic camera sky spot, panoramic camera dust monitoring on the mast, miniature thermal emission spectrometer target calibration and panoramic camera high-sun surveys.

Sol-by-sol summary:

Sol 1256: Opportunity conducted one hour of runout science.

Sol 1257: On this sol, the rover's activities included the following: uplinked on high-gain antenna, panoramic camera wide-range tau, navigation camera tau, navigation camera bitty cloud, panoramic camera soria, front hazard avoidance camera images, rear hazard avoidance camera images, navigation camera images, panoramic camera wide-range tau, panoramic camera horizon survey, panoramic camera calibration target, mast dust monitoring, miniature thermal emission spectrometer calibration target and panamoric camera high-sun survey.

Sol 1258: Opportunity conducted 45 minutes of of runout science.

Sol 1259: On this sol, the rover did 30 minutes of runout science and completed a UHF data downlink.

Sol 1260: Opportunity conducted 45 minutes of runout science.

Sol 1261: Opportunity's activities included the following: uplink on high-gain antenna, engineering navigation camera tau, panoramic camera wide range tau, panoramic camera soria calibration target, front hazard avoidance camera images, rear hazard avoidance camera images, navigation camera images, panoramic camera high-sun sky survey, pancam wide range tau and UHF downlink.

Sol 1262: The rover did 30 minutes of runout science and completed a UHF downlink.

Sol 1263: Opportunity conducted 45 minutes of runout science.

Sol 1264: On this sol, the rover's activities included the following: uplink on the high-gain antenna, engineering navigation camera tau, panoramic camera wide-range tau, panoramic camera soria calibration target, front hazard avoidance camera images, rear hazard avoidance camera images, panoramic camera sky thumbs and panoramic camera wide-range tau.

Sol 1265: 45 minutes of runout science and UHF downlink.

Odometry:

Opportunity's odometery is 11,462.94 meters (7.12 miles) as of the last drive on sol 1232.

Opportunity Update Archive

Source: NASA/JPL - MER - Status

Legends never fall, but their records beckon to be broken. NASA's rover Spirit recently overtook the classic Viking 2 Lander's spot as the second-longest-lasting spacecraft on the surface of Mars: 1290 sols (martian days) and counting! Its twin Opportunity is climbing the charts, next up to take its place in the top three. But better watch out -- the next generation of rovers are designed to be "far out" and "super-charged," traveling much farther and lasting much longer. So, stay tuned for more fab feats to come!.

Image credit: NASA/JPL

Source: NASA/JPL - Mars Exploration Rovers - Spirit

Mars Exploration Rover Status Report: Rovers Resume Driving

After six weeks of hunkering down during raging dust storms that limited solar power, both of NASA's Mars Exploration Rovers, Spirit and Opportunity, have resumed driving.

Opportunity advanced 13.38 meters (44 feet) toward the edge of Victoria Crater on Aug. 21. Mission controllers were taking advantage of gradual clearing of dust from the sky while also taking precautions against buildup of dust settling onto the rover.


Image above: NASA's Opportunity rover used its front hazard-identification
camera to obtain this image at the end of a drive on the rover's 1,271st sol,
or Martian day (Aug. 21, 2007).
Image credit: NASA/JPL-Caltech

"Weather and power conditions continue to improve, although very slowly for both rovers," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif, project manager for the rovers. With the improved energy supplies, both rovers are back on schedule to communicate daily. Opportunity had previously been conserving energy by going three or four days between communications.

No new storms have been lifting dust into the air near either solar-powered rover in the past two weeks. Skies are gradually brightening above both Spirit and Opportunity. "The clearing could take months," said rover Project Scientist Bruce Banerdt. "There is a lot of very fine material suspended high in the atmosphere."

As that material does settle out of the air, the powdery dust is accumulating on surfaces such as the rovers' solar panels and instruments. More dust on the solar panels lessens the panels' capacity for converting sunlight to electricity, even while more sunlight is getting through the clearer atmosphere.

Opportunity's daily supply of electricity from its solar panels reached nearly 300 watt-hours on Aug. 23. That is more than twice as much as five weeks ago, but still less than half as much as two months ago. It is enough to run a 100-watt bulb for three hours.

One reason the rover team chose to drive Opportunity closer to the crater rim was to be prepared, if the pace of dust accumulation on the solar panels increases, to drive onto the inner slope of the crater. This would give the rover a sun-facing tilt to maximize daily energy supplies. The drive was also designed to check performance of the rover's mobility system, so it included a turn in place and a short drive backwards.

The next day, a favorable wind removed some dust from Opportunity's solar panels, providing a boost of about 10 percent in electric output. This forestalled the need to hurry to a sun-facing slope. The team is still excited to get Opportunity inside Victoria Crater to examine science targets on the inner slope that were identified in June, shortly before dust storms curtailed rover activities. An estimate of how soon Opportunity will enter the crater will depend on assessments in coming days of how dust may be affecting the instruments and of how much energy will be available.

On Spirit, dust on the lens of the microscopic imager has slightly reduced image quality for that instrument, although image calibration can compensate for most of the contamination effects. The team is experimenting with ways to try dislodging the dust on the lens. Spirit's solar arrays are producing about 300 watt hours per day as dust accumulation on them offsets clearing skies. Spirit drove 42 centimeters (17 inches) backwards on Aug. 23 to get in position for taking images of a rock that it had examined with its Moessbauer spectrometer. The rover team is planning additional drives for Spirit to climb onto a platform informally named "Home Plate."


Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278/5011

Source: NASA - Missions - Mars Rovers

Opportunity's First Drive in Six Weeks



NASA's Mars Exploration Rover Opportunity used its front hazard-identification camera to obtain this image at the end of a drive on the rover's 1,271st sol, or Martian day (Aug. 21, 2007).

Due to sun-obscuring dust storms limiting the rover's supply of solar energy, Opportunity had not driven since sol 1,232 (July 12, 2007). On sol 1,271, after the sky above Opportunity had been gradually clearing for more than two weeks, the rover rolled 13.38 meters (44 feet). Wheel tracks are visible in front of the rover because the drive ended with a short test of driving backwards. Opportunity's turret of four tools at the end of the robotic arm fills the center of the image. Victoria Crater, site of the rover's next science targets, lies ahead.

Image Credit: NASA/JPL-Caltech

+ Larger view

Source: NASA - Missions - Mars Rovers - Images

Wadda you know....they made it through the dust storms......Thanks for posting Waspie...

The University of Chicago press release is reproduced below:

By Steve Koppes
News Office


Mars rover scientists have launched a new long-term study on the Martian atmosphere with the alpha particle X-ray spectrometer, an instrument that was originally developed at Chicago.

Thanasis Economou, Senior Scientist at the University’s Enrico Fermi Institute, suggested the new study after observing that the APXS instruments aboard NASA’s twin Mars rovers, Spirit and Opportunity, had recorded fluctuations in the argon composition of the Martian atmosphere. “The amount of argon in the atmosphere is changing constantly,” Economou said.


A view from NASA’s Opportunity rover of Cape St. Vincent, one
of the many promontories that jut out from the walls of Victoria
Crater on Mars. Opportunity will descend into the crater in coming
weeks carrying the Alpha Particle X-ray Spectrometer, an
instrument that was originally developed at the University. This
image was taken by Opportunity’s panoramic camera on Sunday,
May 6, 2007. It is presented in false color to accentuate differences
in surface materials.


An orbital view of Victoria Crater on Mars, showing the path of
the Opportunity rover along the north rim. Mars rover scientists
have launched a new long-term study on the Martian atmosphere
with the Alpha Particle X-ray Spectrometer, an instrument that
was originally developed at the University of Chicago. This orbital
view was acquired by the High-Resolution Imaging Science
Experiment camera on the Mars Reconnaissance Orbiter.
(Image courtesy of NASA/JPL-Caltech/UofA/USGS)

During warmer seasons, approximately 95 percent of the Martian atmosphere consists of carbon dioxide. Nitrogen accounts for almost 3 percent and argon for less than 2 percent. But when winter sets in at one of the poles, carbon dioxide freezes out of the atmosphere to form a polar cap, causing a low-pressure system that moves air toward the pole.

Argon stays in the atmosphere and becomes enhanced because it freezes at a much lower temperature, Economou said. An instrument on NASA’s Odyssey orbiter around Mars found that on the south pole of Mars during the winter, the argon concentration is six times higher than during the warmer seasons.

“The amount of argon that comes with the air mass stays in the atmosphere,” he explained. “Carbon dioxide drops, so the ratio of argon to carbon dioxide is increasing constantly until the next season.”

With the onset of warmer spring and summer temperatures, the frozen carbon dioxide evaporates back into the atmosphere, causing a high-pressure system that pushes the air mass back toward the equator.

“The fact that we see a signal at all means there’s a lot of mixing between the polar air and the air at the tropics,” said Ray Pierrehumbert, the Louis Block Professor in Geophysical Sciences and the College, who specializes in the evolution of climate on Earth and Mars. “It gives you a way of inferring aspects of the Martian circulation that you can’t observe at all with any other instrument that’s out there,” he said.

Scientists are coupling the APXS measurements with additional data collected by the orbiting Mars Odyssey spacecraft. The APXS measures the number of argon atoms at the rover’s location between the instrument and the ground—a distance of a couple of centimeters (a few inches). Odyssey’s gamma-ray spectrometer, meanwhile, measures the argon in a column of air extending from the upper atmosphere to the Martian surface, but over an area spanning several hundred kilometers (a couple hundred miles).

Spirit and Opportunity landed on Mars in January 2004. Until now, their APXS instruments have focused on measuring the chemical content of rocks and dust sitting on the ground. During the mission’s first 90 days, for example, Opportunity’s APXS contributed to the identification and analysis of abundant sulfate salts and other minerals suggestive of once-moist environments on the vast plain known as Meridiani Planum.

“It means that at some point the site was soaked with liquid water,” Economou said.

Opportunity’s APXS also performed a key analysis of the first meteorite ever discovered on Mars. When Opportunity encountered Heat Shield rock in 2005, “it looked like a meteorite, but it was confirmed with the APXS,” Economou said. It was the first of at least four meteorites that Opportunity has discovered.

“If you go to Antarctica you find lots of them because you can spot them,” he said. “On Mars also, when you have these large, flat areas that have just sand and sand dunes, nothing else, and you now see some suspicious rock, you know that it’s not from there.” Either it is debris that has been ejected from an impact crater or a meteorite.

In recent months, the APXS on the Spirit rover measured the composition of soils consisting of 90 percent pure silica, which could have formed in a hot-spring environment or some other process involving water. The finding presents some of the best evidence yet that water once existed at Gusev Crater.

“This is a remarkable discovery,” said Cornell University’s Steve Squyres, who heads the Mars rovers’ science instruments team. “The fact that we found something this new and different after nearly 1,200 days on Mars makes it even more remarkable. It makes you wonder what else is still out there.”

Opportunity now has traveled more than six miles through some difficult sandy terrain to reach Victoria Crater, which measures half a mile in diameter. Rolling up to the edge of the crater, the rover has taken images of the layered sediments, various rock types and accumulations of sand visible at the base of the walls.

NASA engineers have scouted a possible route that Opportunity could safely follow onto the crater floor. A dust storm in the region has delayed plans to send Opportunity into the crater.

“This is a magnificent crater with a lot of exposed bedrocks and walls showing geologic detail with extensive layering that makes the team geologist very happy,” Economou said. “What you can see is amazing.”

Source: University of Chicago press release

The Cornell University press release is reproduced below:

Aug. 29, 2007

The mighty Mars rovers Spirit and Opportunity continue to persevere in brutal conditions, as revealed in images of the sun they are sending home. The images show how opaque the Martian atmosphere has been in the face of a raging, two-month dust storm.



NASA/JPL/Cornell/Planetary Society
Photos of the sun taken by the rover Opportunity show how dusty the Martian
atmosphere is on various days this summer.

To understand the gravity of the storm, engineers and astronomers monitor the situation by examining the images of the sun and measuring the amount of dust or the opacity of the atmosphere.

Emily Lakdawalla of the Planetary Society assembled the mosaic of images, which were taken daily by the panoramic cameras (Pancams) on both rovers, Spirit and Opportunity. The images were calibrated by students in Cornell's MarsLab image-processing facility and made available through collaboration with Jim Bell, Cornell professor of astronomy and the principal investigator on the rovers' Pancam imaging team.

"Emily's mosaics are quite remarkable. They show a rover's-eye view of the storm getting worse, and this little light bulb we call the sun getting dimmer and dimmer and dimmer as the dust clouds built up," said Bell.

Since June, a massive dust storm has engulfed much of the Martian surface. The storm has put the rovers in danger, as they depend upon solar power to run during the day and to survive the harsh, cold Martian nights. As dust clouds block the sunlight and dust settles on the solar panels, the rovers' energy is depleted. Only wind can remove the dust, Bell said.


NASA/JPL/Cornell/Planetary Society
An animation of the photos above.

For the rover Spirit, the Jet Propulsion Laboratory (JPL) in Pasadena, Calif., reports that even though the Martian sky above Gusev Crater is clearing, solar power levels remained fairly low and constant dust now appears to be accumulating on the solar panels. Between sol -- a Martian day -- 1283 (Aug. 12) and sol 1286 (Aug. 16), the atmosphere cleared by about 35 percent, leading to daily energy levels of about 300 watt-hours (the amount of energy needed to light a 100-watt bulb for three hours). Typical levels before the dust storms were around 700 to 900 watt-hours for the rovers.

On the other side of Mars, Opportunity, now waiting to enter Victoria Crater from the rim, is currently experiencing its lowest power levels to date. The sky was so dark in mid-July that less than 200 watt-hours of daily energy was available, according to JPL. But skies are slowly clearing, offering hope that the rover will be ready for a descent into the crater soon. Opportunity benefited from wind blowing some dust off solar panels on Aug. 22. Under gradually clearing skies, Opportunity's solar panels were producing about 300 watt hours daily by Aug. 24.

The Jet Propulsion Laboratory, a division of the California Institute of Technology, Pasadena, manages the Mars Exploration Rover Project for the NASA Science Mission Directorate, Washington, D.C.



Source: Cornell University - Chronicle Online

The press release is reproduced below:

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown@nasa.gov

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

RELEASE: 07-187

Mars Rovers Survive Severe Dust Storms, Ready for Next Objectives

PASADENA, Calif. --Two months after sky-darkening dust from severe storms nearly killed NASA's Mars exploration rovers, the solar-powered robots are awake and ready to continue their mission. Opportunity’s planned descent into the giant Victoria Crater was delayed, but now the rover is preparing to drive into the half-mile diameter crater as early as Sept. 11.

Spirit, Opportunity's rover twin, also survived the global dust storm. The rovers are 43 months into missions originally planned to last three months. On Sept. 5, Spirit climbed onto its long-term destination called Home Plate, a plateau of layered bedrock bearing clues to an explosive mixture of lava and water.

"These rovers are tough. They faced dusty winds, power starvation and other challenges -- and survived. Now they are back to doing groundbreaking field work on Mars. These spacecraft are amazing," said Alan Stern, associate administrator of NASA's Science Mission Directorate, Washington.

Victoria Crater contains an exposed layer of bright rocks that may preserve evidence of interaction between the Martian atmosphere and surface from millions of years ago, when the atmosphere might have been different from today's. Victoria is the biggest crater Opportunity has visited.

Martian dust storms in July blocked so much sunlight that researchers grew concerned the rovers' daily energy supplies could plunge too low for survival. Engineers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., put Opportunity onto a very low-energy regimen of no movement, few observations and reduced communication with Earth. Skies above both rovers remain dusty but have been clearing gradually since early August.

Dust from the sky has been falling onto both rovers' solar panels, impeding their ability to collect energy from the sun. However, beneficial wind gusts removed some of the new buildup from Opportunity almost as soon as it accumulated.

Opportunity drove to the lip of Victoria Crater in late August and examined possible entry routes. This week, Opportunity has been driving about 130 feet toward its planned entry point. The route will provide better access to a top priority target inside the crater: a bright band of rocks about 40 feet from the rim. "We chose a point that gives us a straight path down, instead of driving cross-slope from our current location," said Paolo Bellutta, a JPL rover driver plotting the route. "The rock surface on which Opportunity will be driving will provide good traction and control of its path into the crater."

For its first foray into the crater, Opportunity will drive just far enough to get all six wheels in; it will then back out and assess slippage on the inner slope. "Opportunity might be ready for that first 'toe dip' into the crater as early as next week," said JPL's John Callas, rover project manager. "In addition to the drives to get to the entry point, we still need to conduct checkouts of two of Opportunity's instruments before sending the rover into the crater."

The rover team plans to assess if dust has impaired use of the microscopic imager. If that tool is working, the team will use it to observe whether a scanning mirror for the miniature thermal emission spectrometer (Mini-TES) can function accurately. This mirror is high on the rover's camera mast. It reflects infrared light from the landscape to the spectrometer at the base of the mast, and it also can be positioned to close the hole in the mast as protection from dust. The last time the spectrometer was used, some aspects of the data suggested the instrument may have been viewing the inside of the mast instead of the Martian landscape.

"If the dust cover or mirror is no longer moving properly, we may have lost the ability to use that instrument on Opportunity," said Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers' science instruments. "It would be the first permanent loss of an instrument on either rover. But we'll see."

The instrument already has provided extensive valuable information about rocks and soils in the Meridiani region where Opportunity works. "Mini-TES has told us a lot about the rocks and soils at Meridiani, but we've learned that the differences among Meridiani rocks are often too subtle for it to distinguish," Squyres said. "The same instrument on Spirit, at Gusev Crater, has a much more crucial role for us at this point in the mission because there is such diversity at Gusev." Researchers will rely heavily on a different type of instrument, Opportunity's alpha particle X-ray spectrometer, for analysis of rocks at the bright-band target layer in the crater.

For images and information about the rovers, visit:


Source: NASA Press Release 07-187

Mars Exploration Rover Status Report: Opportunity Takes a Dip Into Victoria Crater

Today, NASA's Mars Exploration Rover Opportunity entered Victoria Crater for the first time. It radioed home information via a relay by NASA's Mars Odyssey orbiter, reporting its activities for the day. Opportunity drove far enough in -- about four meters (13 feet) -- to get all six wheels past the crater rim. Then it backed uphill for about three meters (10 feet). The driving commands for the day included a precaution for the rover to stop driving if its wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater.


Image above: NASA's Mars Exploration Rover Opportunity entered
Victoria Crater during the rover's 1,291st Martian day, or sol, (Sept. 11,
2007).
Image credit: NASA/JPL-Caltech

"We will do a full assessment of what we learned from the drive today and use that information to plan Opportunity's descent into the crater," said John Callas, rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. Once Opportunity begins its extended exploration inside the crater, the rover will investigate layered rocks exposed on the interior slope.

Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278/5011

Source: NASA - Missions - MER

Opportunity's First Dip into Victoria Crater


NASA's Mars Exploration Rover Opportunity entered Victoria Crater during the rover's 1,291st Martian day, or sol, (Sept. 11, 2007). The rover team commanded Opportunity to drive just far enough into the crater to get all six wheels onto the inner slope, and then to back out again and assess how much the wheels slipped on the slope. The driving commands for the day included a precaution for the rover to stop driving if the wheels were slipping more than 40 percent. Slippage exceeded that amount on the last step of the drive, so Opportunity stopped with its front pair of wheels still inside the crater. The rover team planned to assess results of the drive, then start Opportunity on an extended exploration inside the crater.

This wide-angle view taken by Opportunity's front hazard-identification camera at the end of the day's driving shows the wheel tracks created by the short dip into the crater. The left half of the image looks across an alcove informally named "Duck Bay" toward a promontory called "Cape Verde" clockwise around the crater wall. The right half of the image looks across the main body of the crater, which is 800 meters (half a mile) in diameter.

Image Credit: NASA/JPL-Caltech

+ Larger view

Source: NASA - Missions - Mars Rovers - Images

Mars Exploration Rover Status Report: Opportunity Begins Sustained Exploration Inside Crater

NASA's Mars Exploration Rover Opportunity finished the last step of a test in-and-out maneuver checking wheel slippage at the rim of Victoria Crater today. Then the rover immediately drove back into the crater as the start of a multi-week investigation on the big bowl's inner slope.


Image above: After a finishing an in-and-out maneuver to check wheel
slippage near the rim of Victoria Crater, NASA's Mars Exploration Rover
Opportunity re-entered the crater.
Image credit: NASA/JPL-Caltech

Opportunity started the day with just two of its six wheels inside the rim of Victoria Crater and ended the day's driving about six meters (20 feet) inside the rim.

The mission's first destination inside the crater is a light-toned layer of exposed rock that may preserve evidence of interaction between the Martian atmosphere and surface from millions of years ago. Victoria exposes a taller stack of ancient rock layers than any crater Opportunity has previously visited during the rover's nearly 44 months on Mars. The mission was originally planned for three months.

"We want to maintain a safe egress route out of the crater for Opportunity, and by completing the back-up drive over the sand ripple at the rim, we have confirmed that we have one," said John Callas, Mars rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "Opportunity is now exploring the interior of Victoria Crater.".

Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278/5011

Source: NASA - Missions - MER

Inside Victoria Crater for Extended Exploration


After a finishing an in-and-out maneuver to check wheel slippage near the rim of Victoria Crater, NASA's Mars Exploration Rover Opportunity re-entered the crater during the rover's 1,293rd Martian day, or sol, (Sept. 13, 2007) to begin a weeks-long exploration of the inner slope. Opportunity's front hazard-identification camera recorded this wide-angle view looking down into and across the crater at the end of the day's drive. The rover's position was about six meters (20 feet) inside the rim, in the "Duck Bay" alcove of the crater.

Image Credit: NASA/JPL-Caltech

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Source: NASA - Missions - Mars Rovers - Images

And our OLD friends from NASA continue their assignment...

Thanks Waspie for the info.....Glad to see them still able to continue..

After waiting out a long, cold winter and a global dust storm, Spirit finally has enough power to explore Home Plate the way scientists have been longing to do since they first saw the layered terrain. Why all the excitement? If you were going to look for past water on Mars, there are three good ways: 1) Look for salts left behind from salty water that evaporated; 2) Look for soft, muddy soil frozen in place over time; and, 3) look for signs of volcanic explosions where water contacted hot, molten rock. At "Home Plate" on Mars, scientists have found all three. That's certainly a home run in the search for more clues to the history of water on Mars.

Image credit: NASA/JPL-Caltech

Source: NASA/JPL - Mars Exploration Rovers - Spirit

Opportunity Reaches First Target Inside Crater

NASA's Mars Exploration Rover Opportunity has reached its science team's first destination for the rover inside Victoria Crater, information received from Mars late Tuesday confirms.


Image above: A layer of light-toned rock exposed inside Victoria Crater
in the Meridiani Planum region of Mars.
Image credit: NASA/JPL-Caltech

Opportunity has descended the inner slope of the 800-meter-wide crater (half a mile wide) to a band of relatively bright bedrock exposed partway down. The rover is in position to touch a selected slab of rock with tools at the end of its robotic arm, after safety checks being commanded because the rover is at a 25-degree tilt. Researchers intend to begin examining the rock with those tools later this week.

"This will be the first of several stops within this band of rock," said Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the science payloads on Opportunity and its twin rover, Spirit. "By sampling it at several different levels in the crater, we're hoping to figure out the processes that led to its formation and its very distinctive appearance."

Opportunity drove 2.25 meters (7.38 feet) on Sept. 25 to get the selected flat rock within reach. That was the 1,305th Martian day of a mission originally planned for 90 Martian days. After entering the crater on Sept. 13 for a multi-week investigation of rock exposed inside, the rover advanced toward the bright band with drives of 7.45 meters (24 feet) on Sept. 18, and 2.47 meters (8 feet) on Sept. 22.

"We have completed several successful drives with Opportunity inside Victoria Crater," said John Callas, Mars rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "The rover is experiencing slopes as high as 25 degrees at some places, but wheel slippage has only been around 10 percent."

Spirit, meanwhile, is exploring the top surface of a plateau called "Home Plate," where rocks hold evidence about an explosive combination of water and volcanism. JPL, a division of the California Institute of Technology, Pasadena, manages the Mars Exploration Rover project for the NASA Science Mission Directorate, Washington.


Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278/5011

Dwayne Brown
NASA Headquarters, Washington
202-358-1726

Source: NASA - Missions - Mars Rovers

At Bright Band Inside Victoria Crater

09.26.07

A layer of light-toned rock exposed inside Victoria Crater in the Meridiani Planum region of Mars appears to mark where the surface was at the time, many millions of years ago, when an impact excavated the crater. NASA's Mars Exploration Rover Opportunity drove to this bright band as the science team's first destination for the rover during investigations inside the crater. Opportunity's left front hazard-identification camera took this image just after the rover finished a drive of 2.25 meters (7 feet, 5 inches) during the rover's 1,305th Martian day, or sol, (Sept. 25, 2007). The rocks beneath the rover and its extended robotic arm are part of the bright band.

Victoria Crater has a scalloped shape of alternating alcoves and promontories around the crater's circumference. Opportunity descended into the crater two weeks earlier, within an alcove called "Duck Bay." Counterclockwise around the rim, just to the right of the arm in this image, is a promontory called "Cabo Frio."

Image Credit: NASA/JPL-Caltech

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Source: NASA - Missions - Mars Rovers - Images

Duck Bay, Victoria Crater

09.28.07

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This image taken by the panoramic camera on the Mars Exploration Rover Opportunity shows the view of Victoria Crater from Duck Bay. Opportunity reached Victoria Crater on Sol 951 (September 27, 2006) after traversing 9.28 kilometers (5.77 miles) since her landing site at Eagle Crater. Victoria Crater is roughly 800 meters (one-half mile) wide -- about five times wider than Endurance Crater, and 40 times as wide as Eagle crater. The south face of the 6 meter (20 foot) tall layered Cape Verde promontory can be seen in the left side of the inner crater wall, about 50 meters (about 165 feet) away from the rover at the time of the imaging. The north face of the 15 meter (50 foot) tall stack of layered rocks called Cabo Frio can be seen on the right side of the inner crater wall.

This mosaic was taken on Sols 952 and 953 (September 28 and 29, 2006). There are 30 separate pointings through 6 different filters at each pointing. This mosaic was generated from Pancam's 753 nm, 535 nm, and 482 nm filters. Four versions are available at full resolution: this approximate true color rendering, a false color stretch to enhance subtle color differences in the scene, a stereo anaglyph, which appears three dimensional when viewed through red-blue glasses, and a black and white version presented as a cylindrical projection with geometric seam correction.

Image Credit: NASA/JPL-Caltech

+ High-resolution JPEG (2.8Mb)

Source: NASA - Missions - Mars Rovers - Images

At the end of a long day of exploration, rugged terrain can be mighty daunting. On Mars, NASA's Spirit rover has encountered boulder-strewn slopes, while having less energy due to dust-coated solar panels. Having endured two Martian winters (May-September, 2004 and April-November, 2006), Spirit's handler's have already started scouting out potential locations within driving distance where the rover might survive another southern-hemisphere Martian winter (March-October, 2008). Getting there will take some careful navigating since many of the slopes leading down from the top of "Home Plate" are too steep for the rover to cross safely with its dragging right front wheel.

Image credit: NASA/JPL-Caltech/Cornell

Source: NASA/JPL - Mars Exploration Rovers - Spirit

NASA Extends Operations for Its Long-Lived Mars Rovers

10.15.07

WASHINGTON - NASA is extending, for a fifth time, the activities of the Mars Exploration Rovers, Spirit and Opportunity. The decision keeps the trailblazing mobile robotic pioneers active on opposite sides of Mars, possibly through 2009. This extended mission and the associated science are dependent upon the continued productivity and operability of the rovers.


Image above: As it finished its second Martian year on Mars, NASA's
Mars Exploration Rover Spirit was beginning to examine a group of
angular rocks given informal names corresponding to peaks in the
Colorado Rockies.
Image credit: NASA/JPL-Caltech

"We are extremely happy to be able to further the exploration of Mars. The rovers are amazing machines, and they continue to produce amazing scientific results operating far beyond their design life," said Alan Stern, associate administrator for NASA's Science Mission Directorate, Washington.

The twin rovers landed on Mars in January 2004, 45 months ago, on missions originally planned to last 90 days. In September, Opportunity began descending into Victoria Crater in Mars' Meridiani Planum region. At approximately 800 meters wide (half a mile) and 70 meters deep (230 feet), it is the largest crater the rover has visited. Spirit climbed onto a volcanic plateau in a range of hills that were on the distant horizon from its landing site.

"After more than three-and-a-half years, Spirit and Opportunity are showing some signs of aging, but they are in good health and capable of conducting great science," said John Callas, rover project manager at NASA's Jet Propulsion Laboratory, Pasadena, Calif.

The rovers each carry a suite of sophisticated instruments to examine the geology of Mars for information about past environmental conditions. Opportunity has returned dramatic evidence that its area of Mars stayed wet for an extended period of time long ago, with conditions that could have been suitable for sustaining microbial life. Spirit has found evidence in the region it is exploring that water in some form has altered the mineral composition of some soils and rocks.


Image above: NASA Mars Exploration
Rover Opportunity used its front hazard-
indentification camera to capture this wide-
angle view of its robotic arm extended to a
rock in a bright-toned layer inside Victoria
Crater.
Image credit: NASA/JPL-Caltech

To date, Spirit has driven 7.26 kilometers (4.51 miles) and has returned more than 102,000 images. Opportunity has driven 11.57 kilometers (7.19 miles) and has returned more than 94,000 images.

Among the rovers' many other accomplishments:

- Opportunity has analyzed a series of exposed rock layers recording how environmental conditions changed during the times when the layers were deposited and later modified. Wind-blown dunes came and went. The water table fluctuated.

- Spirit has recorded dust devils forming and moving. The images were made into movie clips, providing new insight into the interaction of Mars' atmosphere and surface.

- Both rovers have found metallic meteorites on Mars. Opportunity discovered one rock with a composition similar to a meteorite that reached Earth from Mars.

JPL manages the rovers for NASA's Science Mission Directorate. JPL is a division of the California Institute of Technology in Pasadena.

For images and information about the rovers, visit: www.nasa.gov/rovers.


Media contacts:
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278

Dwayne Brown
NASA Headquarters, Washington
202-358-1726

2007-120

Source: NASA - Missions - MER

Spirit Begins Third Martian Year

10.15.07

As it finished its second Martian year on Mars, NASA's Mars Exploration Rover Spirit was beginning to examine a group of angular rocks given informal names corresponding to peaks in the Colorado Rockies. A Martian year -- the amount of time it takes Mars to complete one orbit around the sun -- lasts for 687 Earth days. Spirit completed its second Martian year on the rover's 1,338th Martian day, or sol, corresponding to Oct. 8, 2007.

Two days later, on sol 1,340 (Oct. 10, 2007), Spirit used its front hazard-identification camera to capture this wide-angle view of its robotic arm extended to a rock informally named "Humboldt Peak." For the rocks at this site on the southern edge of the "Home Plate" platform in the inner basin of the Columbia Hills inside Gusev Crater, the rover team decided to use names of Colorado peaks higher than 14,000 feet. The Colorado Rockies team of the National League is the connection to the baseball-theme nomenclature being used for features around Home Plate.

The tool facing Spirit on the turret at the end of the robotic arm is the Moessbauer spectrometer.

Image Credit: NASA/JPL-Caltech

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Source: NASA - Missions - Mars Rovers - Images

Opportunity at Work Inside Victoria Crater

10.15.07

NASA Mars Exploration Rover Opportunity used its front hazard-indentification camera to capture this wide-angle view of its robotic arm extended to a rock in a bright-toned layer inside Victoria Crater.

The image was taken during the rover's 1,322nd Martian day, or sol (Oct. 13, 2007).

Victoria Crater has a scalloped shape of alternating alcoves and promontories around the crater's circumference. Opportunity descended into the crater two weeks earlier, within an alcove called "Duck Bay." Counterclockwise around the rim, just to the right of the arm in this image, is a promontory called "Cabo Frio."

Image Credit: NASA/JPL-Caltech

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Source: NASA - Missions - Mars Rovers - Images

Opportunity's Second Martian Birthday at Cape Verde

10.29.07

A promontory nicknamed "Cape Verde" can be seen jutting out from the walls of Victoria Crater in this approximate true-color picture taken by the panoramic camera on NASA's Mars Exploration Rover Opportunity. The rover took this picture on martian day, or sol, 1329 (Oct. 20, 2007), more than a month after it began descending down the crater walls – and just 9 sols shy of its second Martian birthday on sol 1338 (Oct. 29, 2007). Opportunity landed on the Red Planet on Jan. 25, 2004. That's nearly four years ago on Earth, but only two on Mars because Mars takes longer to travel around the sun than Earth. One Martian year equals 687 Earth days.

The overall soft quality of the image, and the "haze" seen in the lower right portion, are the result of scattered light from dust on the front sapphire window of the rover's camera.

This view was taken using three panoramic-camera filters, admitting light with wavelengths centered at 750 nanometers (near infrared), 530 nanometers (green) and 430 nanometers (violet).

Image Credit: NASA/JPL-Caltech/Cornell

+ High-resolution JPG (2.1Mb)

Source: NASA - Missions - Mars Rovers - Images

Cape Verde in False Color

10.29.07

A promontory nicknamed "Cape Verde" can be seen jutting out from the walls of Victoria Crater in this false-color picture taken by the panoramic camera on NASA's Mars Exploration Rover Opportunity. The rover took this picture on martian day, or sol, 1329 (Oct. 20, 2007), more than a month after it began descending down the crater walls – and just 9 sols shy of its second Martian birthday on sol 1338 (Oct. 29, 2007). Opportunity landed on the Red Planet on Jan. 25, 2004. That's nearly four years ago on Earth, but only two on Mars because Mars takes longer to travel around the sun than Earth. One Martian year equals 687 Earth days.

This view was taken using three panoramic-camera filters, admitting light with wavelengths centered at 750 nanometers (near infrared), 530 nanometers (green) and 430 nanometers (violet).

Image Credit: NASA/JPL-Caltech/Cornell

+ High-resolution JPG (2.7Mb)

Source: NASA - Missions - Mars Rovers - Images

Tantalizing vistas to the south beyond the edge of "Home Plate," shown here in 3D, will have to wait for another spring, if NASA's Mars rover Spirit survives until then. Though winter is months away, scientists are looking for a safe winter haven while the rover still has enough power to drive. Team members have concerns because Spirit is approaching its third Martian winter with more dust on its solar panels than it had during its first two winters. The dust lessens the panels' ability to convert sunlight into the electricity that Spirit needs for operations and survival.

Spirit's goal is to reach a slope on the north side of Home Plate that will tilt the rover's solar panels to the north about 25 degrees, facing the sun. The hope is that this will keep the rover's electronics alive during the cold, dark winter.

Image credit: NASA/JPL-Caltech/Cornell

Source: NASA/JPL - Mars Exploration Rovers - Spirit

If you were a scientist studying Mars and sharing your progress with family and friends, perhaps you would send back digital postcards showing them where you've been. Earthlings have now received a record 200,000 such postcards from NASA's two Mars rovers!

The images enable us to study changes on the red planet, such as subtle variations in color and texture shown here in a ring of rocks inside "Victoria Crater." The light-colored rocks are interesting because scientists think they may be the original surface before a meteor formed the crater and splattered debris onto it.

Image credit: NASA/JPL-Caltech/Cornell

Source: NASA/JPL - Mars Exploration Rovers - Opportunity

While struggling to reach a winter outpost necessary for survival on Mars, Spirit has been slowed by sand in the bottom of a shallow, bowl-like depression. Spirit's goal is to reach a slope on the north edge of "Home Plate" that will keep its solar panels trained on the Sun.

If the rover can collect enough sunlight to survive, Spirit will continue to study terrain near "Home Plate," which the rover reached after crossing the floor of Gusev Crater and scaling the "Columbia Hills." This map shows the rover's progress from July 2004 to November 2007.

Image credit: NASA/JPL-Caltech/USGS/UNM/High-Resolution Science Imaging Experiment

Source: NASA/JPL - Mars Exploration Rovers - Spirit

December 10, 2007


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In March 2007, NASA's Spirit rover found
a patch of bright-toned soil so rich in silica
that scientists proposed water must have
been involved in concentrating it.
Image credit: NASA/JPL/Cornell
+ Caption and full image

SAN FRANCISCO - Researchers using NASA's twin Mars rovers are sorting out two possible origins for one of Spirit's most important discoveries, while also getting Spirit to a favorable spot for surviving the next Martian winter.

The puzzle is what produced a patch of nearly pure silica -- the main ingredient of window glass -- that Spirit found last May. It could have come from either a hot-spring environment or an environment called a fumarole, in which acidic steam rises through cracks. On Earth, both of these types of settings teem with microbial life.

"Whichever of those conditions produced it, this concentration of silica is probably the most significant discovery by Spirit for revealing a habitable niche that existed on Mars in the past," said Steve Squyres of Cornell University, Ithaca, N.Y., principal investigator for the rovers' science payload. "The evidence is pointing most strongly toward fumarolic conditions, like you might see in Hawaii and in Iceland. Compared with deposits formed at hot springs, we know less about how well fumarolic deposits can preserve microbial fossils. That's something needing more study here on Earth."

Halfway around Mars from Spirit, Opportunity continues adding information about types of wet environments on ancient Mars other than hot springs or fumaroles. It is examining layers exposed inside a crater, but still near the top of a stack of sulfate-rich layers hundreds of meters (yards) thick. Scientists read a history of conditions that evolved from wetter to drier, based on findings by Opportunity and observations of the region by Mars orbiters.

The solar-powered rovers have been active on Mars since January 2004, more than 15 times longer than originally planned. Their third Martian winter will not reach minimum sunshine until June, but Spirit already needs two days of power output to drive for an hour.

"Spirit is going into the winter with much more dust on its solar panels than in previous years," said John Callas of NASA's Jet Propulsion Laboratory, Pasadena, Calif., project manager for the rovers. "The last Martian winter, we didn't move Spirit for about seven months. This time, the rover is likely to be stationary longer and with significantly lower available energy each Martian day."

Dust storms that darkened Martian skies this past June dropped dust onto both rovers. However, gusts cleaned Opportunity's panels, and Opportunity is closer to the equator than Spirit is, so concerns for winter survival focus on Spirit. The team has selected a sun-facing slope of about 25 degrees on the northern edge of a low plateau, "Home Plate," as a safe winter haven for Spirit.

Both rovers resumed productive field work after the June dust storms. Spirit explored the top of Home Plate, in the vicinity of silica-rich soil it discovered before the dust storms hit.

"This stuff is more than 90 percent silica," Squyres said. "There aren't many ways to explain a concentration so high." One way is to selectively remove silica from the native volcanic rocks and concentrate it in the deposits Spirit found. Hot springs can do that, dissolving silica at high heat and then dropping it out of solution as the water cools. Another way is to selectively remove almost everything else and leave the silica behind. Acidic steam at fumaroles can do that. Scientists are still assessing both possible origins. One reason Squyres favors the fumarole story is that the silica-rich soil on Mars has an enhanced level of titanium. On Earth, titanium levels are relatively high in some fumarolic deposits.

Mineral mapping and high-resolution imagery from Mars orbiters are helping scientists put the findings of Spirit and Opportunity into broader geological context. Opportunity's exploration of the Meridiani region has taken advantage of the natural excavations at impact craters to inspect layers extending several meters below the surface of the regional plain. These sulfate-rich layers bear extensive evidence for a wet, acidic past environment. They are a small upper fraction of the sulfate-rich layering exposed elsewhere in Meridiani and examined from orbit.

"We see evidence from orbit for clay minerals under the layered sulfate materials," said Ray Arvidson of Washington University in St. Louis, deputy principal investigator for the rovers' science payload. "They indicate less acidic conditions. The big picture appears to be a change from a more open hydrological system, with rainfall, to more arid conditions with groundwater rising to the surface and evaporating, leaving sulfate salts behind."

JPL, a division of California Institute of Technology, Pasadena, manages the rovers for NASA's Science Mission Directorate.

For images and information about the rovers, visit: _www.nasa.gov/rovers and _http://marsrovers.jpl.nasa.gov.


Media Contact: Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
guy.webster@jpl.nasa.gov

2007-144

Source: NASA/JPL - News Release

The deck of NASA's Mars Exploration Rover Spirit is so dusty that the rover almost blends into the dusty background in this image assembled from frames taken by the panoramic camera (Pancam) during the period from Spirit's Sol 1,355 through Sol 1,358 (Oct. 26-29, 2007).

Dust on the solar panels reduces the amount of electrical power the rover can generate from sunlight each sol. Earlier self-portraits by Spirit, such as one taken on Sol 586, offer a comparison view of cleaner solar panels.

The vertical projection used here produces the best view of the rover deck, though it distorts the ground and antennas somewhat. The eight-pointed star shape near the front of the rover (bottom of the image) marks the location of the camera mast, which is out of view of the Pancam atop the mast.

This mosaic view in approximate true color is a composite of frames taken through the Pancam's filters centered on wavelengths of 600 nanometers, 530 nanometers and 480 nanometers.

Image credit: NASA/JPL-Caltech/Cornell




NASA's Mars Exploration Rover Spirit was crossing northward on a low plateau called "Home Plate" on the 1,386th Martian day, or sol, (Nov. 26, 2007) of Spirit's time on Mars. By that time, nearly 47 months into a mission originally planned to last three months, Spirit had driven 7,435 meters (4.62 miles). From its landing site near the northwest corner of this map, Spirit crossed a plain to reach the Columbia Hills, climbed over the summit of Husband Hill, and descended into the "Inner Basin" of the range, near the southeast corner of the map.

For this map, the yellow line indicating Spirit's route has been overlaid onto a portion of an image taken by the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter on Nov. 22, 2006, That image is catalogued as PSP_001513_1655. The scale bar on the map is 500 meters (1,640 feet) long. North is up.

Image credit: NASA/JPL-Caltech/UA/Cornell/NM Museum of Natural History and Science




Approaching its 47th month of a Mars surface mission originally planned to last three months, NASA's Spirit rover was also approaching the northern edge of a low plateau called "Home Plate." The rover's operators selected an area with north-facing slope there as a destination where Spirit would have its best chance of surviving low-solar-energy conditions of oncoming Martian winter.

The yellow line on this map of the Home Plate area indicates Spirit's route from early February 2006, entering the mapped area from the north (top), to late November 2007, on the western edge of the bright-toned Home Plate plateau. The map covers an area about 160 meters (525 feet) across from west to east. Labels indicate the area intended for Spirit to spend many months spanning the rover's third Martian winter, the site where it spent about seven months (April to November 2006) spanning its second winter, and the site where it lost use of the drive motor for one of its six wheels.

A north-facing slope helps Spirit maximizes electric output from its solar panels during winter months because Spirit is in the southern hemisphere of Mars, so the sun appears only in the northern sky during winter. For the third winter, which will reach its minumum solar-energy days in early June 2008, Spirit faces the challenge of having more dust on its solar panels than it had during its second winter.

The base image for this map is a portion of a color image taken on Jan. 9, 2007,by the High Resolution Imaging Science Experiment camera on NASA's Mars Reconnaissance Orbiter.

Image credit: NASA/JPL-Caltech/UA/Cornell/NM Museum of Natural History and Science




NASA's Mars Exploration Rover Spirit made daily progress in early December 2007 toward the northern edge of a low plateau called "Home Plate." The rover's operators selected an area with north-facing slope there (indicated by the blue-outlined rectangle) as a destination where Spirit would have its best chance of surviving low-solar-energy conditions of oncoming Martian winter.

As indicated by the yellow line tracing the path Spirit has driven, the rover was near the western edge of the plateau on Sol (Martian day) 1,390 of the mission (Nov. 30, 2007), but nearing the northern edge by Sol 1,397 (Dec. 8, 2007).

A north-facing slope helps Spirit maximizes electric output from its solar panels during winter months because Spirit is in the southern hemisphere of Mars, so the sun appears only in the northern sky during winter. For the third winter, which will reach its minumum solar-energy days in early June 2008, Spirit faces the challenge of having more dust on its solar panels than it had during its second winter.

The base image for this map is a portion of a color image taken on Jan. 9, 2007,by the High Resolution Imaging Science Experiment camera on NASA's Mars Reconnaissance Orbiter.

Image credit: NASA/JPL-Caltech/UA/Cornell/NM Museum of Natural History and Science

Source: NASA/JPL - Mars Exploration Rovers - Spirit

"Victoria Crater," about 800 meters (one-half mile) in diameter, has been home ground for NASA's Mars Exploration Rover Opportunity for more 14 of the rover's first 46 months on Mars. This view shows the rover's path overlaid on an image of the crater taken by the High Resolution Imaging Science Experiment on NASA's Mars Reconnaissance Orbiter.

Opportunity first reached the crater's rim on Sept. 27, 2006, during the 951st Martian day, or sol, of the rover's work in the Meridian Planum region of Mars. The rover then explored clockwise about one-fourth of the way around the rim before returning to a point close to its first overlook. On the mission's 1,293rd sol (Sept. 13, 2007), Opportunity began a sustained exploration of the interior of the crater, entering at an alcove called "Duck Bay" on the western side of Victoria.

This traverse map includes Opportunity's route though Sol 1,365 (Nov. 26, 2007). The scale bar is 300 meters (984 feet) long.

Image credit: NASA/JPL-Caltech/University of Arizona/Cornell/Ohio State University

Source: NASA/JPL - Mars Exploration Rovers - Opportunity

Human explorers would be hard pressed to show more persistence than NASA's Mars rover Spirit. After weeks of careful driving with a broken front wheel, Spirit finally made it to a north-facing slope of "Home Plate."

The rover gradually descended over the north edge to get into position, as shown here, tilting its solar panels 13 degrees toward the sinking winter Sun to maximize power. Rover drivers plan to continue nudging Spirit forward, increasing the tilt, to track the Sun as it moves lower in the northern sky.

Image credit: NASA/JPL-Caltech/Hazard avoidance camera

Source: NASA/JPL - Mars Exploration Rovers - Spirit

Another of the best examples of spectacular cross-bedding in Victoria crater are the outcrops at Cape St. Mary, which is an approximately 15 m (45 foot) high promontory located along the western rim of Victoria crater and near the beginning of the rover's traverse around the rim. Like the Cape St. Vincent images, these Pancam super-resolution images have allowed scientists to discern that the rocks at Victoria Crater once represented a large dune field that migrated across this region.

This is a Mars Exploration Rover Opportunity Panoramic Camera image mosaic acquired on sol 1213 (June 23, 2007), and was constructed from a mathematical combination of 32 different blue filter (480 nm) images.

Image credit: NASA/JPL-Caltech/Cornell University




This Mars Exploration Rover Opportunity Pancam "super resolution" mosaic of the approximately 6 m (20 foot) high cliff face of the Cape Verde promontory was taken by the rover from inside Victoria Crater, during the rover's descent into Duck Bay. Super-resolution is an imaging technique which utilizes information from multiple pictures of the same target in order to generate an image with a higher resolution than any of the individual images. Cape Verde is a geologically rich outcrop and is teaching scientists about how rocks at Victoria crater were modified since they were deposited long ago. This image complements super resolution mosaics obtained at Cape St. Mary and Cape St. Vincent and is consistent with the hypothesis that Victoria crater is located in the middle of what used to be an ancient sand dune field. Many rover team scientists are hoping to be able to eventually drive the rover closer to these layered rocks in the hopes of measuring their chemistry and mineralogy.

This is a Mars Exploration Rover Opportunity Panoramic Camera image mosaic acquired on sols 1342 and 1356 (November 2 and 17, 2007), and was constructed from a mathematical combination of 64 different blue filter (480 nm) images.

Image credit: NASA/JPL-Caltech/Cornell University




NASA's Mars Exploration Rover Opportunity rover spent about 300 sols (Martian days) during 2006 and 2007 traversing the rim of Victoria Crater. Besides looking for a good place to enter the crater, the rover obtained images of rock outcrops exposed at several cliffs along the way.

The cliff in this image from Opportunity's panoramic camera (Pancam) is informally named Cape St. Vincent. It is a promontory approximately 12 meters (39 feet) tall on the northern rim of Victoria crater, near the farthest point along the rover's traverse around the rim. Layers seen in Cape St. Vincent have proven to be among the best examples of meter scale cross-bedding observed on Mars to date. Cross-bedding is a geologic term for rock layers which are inclined relative to the horizontal and which are indicative of ancient sand dune deposits. In order to get a better look at these outcrops, Pancam "super-resolution" imaging techniques were utilized. Super-resolution is a type of imaging mode which acquires many pictures of the same target to reconstruct a digital image at a higher resolution than is native to the camera. These super-resolution images have allowed scientists to discern that the rocks at Victoria Crater once represented a large dune field, not unlike the Sahara desert on Earth, and that this dune field migrated with an ancient wind flowing from the north to the south across the region. Other rover chemical and mineral measurements have shown that many of the ancient sand dunes studied in Meridiani Planum were modified by surface and subsurface liquid water long ago.

This is a Mars Exploration Rover Opportunity Panoramic Camera image acquired on sol 1167 (May 7, 2007), and was constructed from a mathematical combination of 16 different blue filter (480 nm) images.

Image credit: NASA/JPL-Caltech/Cornell University

Source: NASA/JPL - Mars Exploration Rovers - Opportunity

NASA's twin Mars Exploration Rovers have been getting smarter as they get older. This view from Opportunity shows the tracks left by a drive executed with more onboard autonomy than has been used on any other drive by a Mars rover.

Opportunity made the curving, 15.8-meter (52-foot) drive during its 1,160th Martian day, or sol (April 29, 2007). It was testing a navigational capability called "Field D-star," which enables the rover to plan optimal long-range drives around any obstacles in order to travel the most direct safe route to the drive's designated destination. Opportunity and its twin, Spirit, did not have this capability until the third year after their January 2004 landings on Mars. Earlier, they could recognize hazards when they approached them closely, then back away and try another angle, but could not always find a safe route away from hazards. Field D-Star and several other upgrades were part of new onboard software uploaded from Earth in 2006. The Sol 1,160 drive by Opportunity was a Martian field test of Field D-Star and also used several other features of autonomy, including visual odometry to track the rover's actual position after each segment of the drive, avoidance of designated keep-out zones, and combining information from two sets of stereo images to consider a wide swath of terrain in analyzing the route.

Two days later, on Sol 1,162, (May 1, 2007), Opportunity was still at the location it reached during that drive, and the rover's panoramic camera (Pancam) took the exposures combined into this image.

Victoria Crater is in the background, at the top of the image. The Sol 1,160 drive began at the place near the center of the image where tracks overlap each other. Tracks farther away were left by earlier drives nearer to the northern rim of the crater. For scale, the distance between the parallel tracks left by the rover's wheels is about 1 meter (39 inches) from the middle of one track to the middle of the other. The rocks in the center foreground are roughly 7 to 10 centimeters (3 to 4 inches) tall. The rover could actually drive over them easily, but for this test, Settings in the onboard hazard-detection software were adjusted to make these smaller rocks be considered dangerous to the rover. The patch of larger rocks to the right was set as a keep-out zone. The location from which this image was taken is where the rover stopped driving to communicate with Earth. A straight line from the starting point to the destination would be 11 meters (36 feet). Opportunity plotted and followed a smoothly curved, efficient path around the rocks, always keeping the rover in safe areas.

This view combines separate images taken through the Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers to produce an approximately true-color panorama.

Image credit: NASA/JPL-Caltech/Cornell University



This view combines separate images taken through the Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

Image credit: NASA/JPL-Caltech/Cornell University


Source: NASA/JPL - Mars Exploration Rovers - Opportunity

NASA'S Mars Exploration Rover Spirit captured this westward view from atop a low plateau where Sprit spent the closing months of 2007.

After several months near the base of the plateau called "Home Plate" in the inner basin of the Columbia Hills range inside Gusev Crater, Spirit climbed onto the eastern edge of the plateau during the rover's 1,306th Martian day, or sol, (Sept. 5, 2007). It examined rocks and soils at several locations on the southern half of Home Plate during September and October. It was perched near the western edge of Home Plate when it used its panoramic camera (Pancam) to take the images used in this view on sols 1,366 through 1,369 (Nov. 6 through Nov. 6, 2007). With its daily solar-energy supply shrinking as Martian summer turned to fall, Spirit then drove to the northern edge of Home Plate for a favorable winter haven. The rover reached that northward-tilting site in December, in time for the fourth Earth-year anniversary of its landing on Mars. Spirit reached Mars on Jan. 4, 2004, Universal Time (Jan. 3, 2004, Pacific Standard Time). It landed at a site at about the center of the horizon in this image.

This panorama covers a scene spanning left to right from southwest to northeast. The western edge of Home Plate is in the foreground, generally lighter in tone than the more distant parts of the scene. A rock-dotted hill in the middle distance across the left third of the image is "Tsiolkovski Ridge," about 30 meters or 100 feet from the edge of Home Plate and about that same distance across. A bump on the horizon above the left edge of Tsiolkovski Ridge is "Grissom Hill," about 8 kilometers or 5 miles away. At right, the highest point of the horizon is "Husband Hill," to the north and about 800 meters or half a mile away.

This view combines separate images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers. It is presented in a false-color stretch to bring out subtle color differences in the scene.

Image credit: NASA/JPL-Caltech/Cornell University



This view combines separate images taken through Pancam filters centered on wavelengths of 753 nanometers, 535 nanometers and 432 nanometers to produce an approximately true-color panorama.

Image credit: NASA/JPL-Caltech/Cornell University



NASA'S Mars Exploration Rover Spirit captured this westward view from atop a low plateau where Sprit spent the closing months of 2007. The view combines a stereo pair and appears three-dimensional when seen through blue-red glasses.

Image credit: NASA/JPL-Caltech/Cornell University

Source: NASA/JPL - Mars Exploration Rovers - Spirit