On sol 168, rover planners commanded Spirit to "bump" backward, into a position where the rock abrasion tool could make contact with Pot-of-Gold. This was successful, and Spirit spent the rest of the time taking images of the surrounding area with its panoramic and navigation cameras. On sol 169, Spirit successfully operated its rock abrasion tool on Pot-of-Gold, grinding away the top .2 millimeters (.008 inches) of rock from the high points. The procedure took 1 hour and 45 minutes. Pot-of-Gold posed a special challenge to the rover team because it is quite small -- only slightly larger than the rock abrasion tool instrument itself. The rock abrasion tool inflicts about 6.8 kilograms (15 pounds) of pressure on its rock targets, and smaller rocks aren't necessarily stable enough to resist this.

Before and after pictures of Pot-of-Gold showed that the rock was moved by the rock abrasion tool procedure. That movement, plus possible slippage where the tool contacts the rock, resulted in only intermittent contact during the grinding operation. After the grind was complete, Spirit placed the alpha particle X-ray spectrometer on the freshly exposed area in preparation for an operation later that night.

On Sol 170, Spirit awoke to stop the alpha particle X-ray integration, took miniature thermal emission spectrometer and panoramic camera images of some local track marks, took more microscopic images of the newly exposed Pot-of-Gold, then placed the Moessbauer instrument on the site for a 21-hour overnight observation.

Daily Update - 6/29/04
RAT Hops from 'Virginia' to 'London'
Opportunity Status for sol 144-149

While Opportunity is hard at work inside "Endurance Crater," engineers at JPL are busy testing engineering models in the Lab's simulated martian environment. A tilt platform is being used to determine Opportunity's ability to climb back up over the "curb" below its current location.

On sol 144, Opportunity completed the Moessbauer spectrometer integration on the rock abrasion tool hole on the "Cobble Hill" area. Microscopic images were also collected.

Sol 145 was a busy day, with the rover collecting more post-rock abrasion tool Cobble Hill and pre-"Virginia" microscopic images. The tool then bored a 4.3-millimeter (0.17 inches) hole in Virginia. Deep sleep mode was invoked for the overnight hours.

Sol 146 was used to examine the newly-abraded hole with the microscopic imager and the alpha particle X-ray spectrometer.

On sol 147 the rover performed a long Moessbauer spectrometer integration on Virginia and completed some remote sensing from its location in the crater. After relaying the data through both Mars Global Surveyor and Mars Odyssey, Opportunity went into deep sleep mode for the night.

"London" was Opportunity's target on sol 148. The rock abrasion tool ground a 4.5-millimeter (0.18 inches) hole in the rock. The alpha particle X-ray spectrometer was then placed on the hole for integration.

On sol 149 the rover continued to scrutinize London with the alpha particle X-ray spectrometer and the microscopic imager. A Moessbauer spectrometer integration was initiated and will be completed on sol 150. Deep sleep mode was invoked for the overnight hours.

Daily Update - 6/25/04
Edging Up on 'Pot-of-Gold'
Spirit Status for sol 164-166

Spirit spent the last few sols getting into position on the rock target "Pot-of-Gold" for an upcoming grind with the rock abrasion tool. This repositioning has not been easy due to slippage in the sandy-sloped terrain at the base of the "Columbia Hills"

On sol 164, Spirit completed an overnight alpha particle X-ray spectrometer observation on Pot-of-Gold and then gathered additional microscopic images of the rock. In the afternoon, rover planners tried to reposition Spirit from a heading of about 170 degrees to a heading of about 95 degrees to improve the instrument deployment device positioning on Pot-of-Gold for the upcoming rock abrasion tool work. The planned traverse sent Spirit past Pot-of-Gold, down a slope on the west side of "Hank's Hollow," then turned the rover to re-approach at the desired heading. The slope and slippage was greater then expected, leaving the rover at a westerly tilt of 19 degrees and almost 2 meters (6.6 feet) away from the target.

Spirit worked toward getting into position in front of Pot-of-Gold on sol 165, but given the slippage and need to avoid overshooting the target, engineers anticipated it would take at least two sols to get properly repositioned. Unfortunately, the drive made less progress than desired due in part to a collection of rocks encountered by the left rear wheel.

On sol 166, Spirit took advantage of its current position and used the gathered Moessbauer data and microscopic images of the soil in front of it before continuing the hill climb. Spirit’s front wheels made it over the crest, leaving the rover at about a 13-degree tilt and still about 1 meter (3.3 feet) from Pot-of-Gold.

Daily Update - 6/23/04
'Pot-of-Gold' Revealed
Spirit Status for sol 161-163

Spirit currently sits at the base of the "Columbia Hills" in an area called the "Hank Moore Hollow." This area has a collection of intriguing rocks on its rim, one of which, "Pot-of-Gold," will be the first target for scientists’ observations.

Spirit used the microscopic imager to get an up close view of Pot-of-Gold on sol 161, but unfortunately, the images were out of focus. Rover planners attribute the blurry shots to a lower than expected rock contact prior to the imaging sequence. Spirit did successfully acquire Moessbauer observations of Pot-of-Gold on this sol.

On sol 162, Spirit was commanded to retake the microscopic images of Pot-of-Gold and do extensive observations with the Moessbauer and alpha particle X-ray spectrometer instruments. The microscopic images were successfully obtained, but a positioning fault of the instrument deployment device prevented the Moessbauer and alpha particle X-ray spectrometer observations from executing.

Spirit successfully completed the work with its instrument deployment device on sol 163, and took some additional microscopic images of Pot-of-Gold.

Daily Update - 6/22/04
Edging Down ‘Endurance’
Opportunity Status for sol 141-143

Opportunity is showing no signs of middle age as it continues to work in "Endurance Crater." The rover has spent the last few sols inching farther down into the crater, making observations and pushing the limits. Managing resources as the rover’s tilt angle changes is challenging and keeps the rover planning team very busy.

On sol 141 Opportunity completed post-rock abrasion tool Moessbauer spectrometer observations on the rock called "Tennessee." Having spent the last four sols investigating Tennessee, Opportunity stowed its arm and moved deeper into Endurance Crater. A 0.70-meter (2.3 feet) drive positioned the vehicle to begin observations on the first contact point, a transition between two different geologic layers. As it turns out, after arriving at the rover’s new location and taking images, there appears to be not one contact point, but three contact points all within reach of the arm. Opportunity then performed 2.5 hours of remote observations using the panoramic camera and miniature thermal emission spectrometer. The rover then went into deep sleep mode for the night.

On sol 142 Opportunity begin another series of microscopic imager observations on three different targets: "Bluegrass," "Siula Grande" and "Churchill." The rover then performed alpha particle X-ray spectrometer and Moessbauer spectrometer integrations overnight.

On sol 143 Opportunity again used its rock abrasion tool, but not without some consternation from the uplink team. In order to grind using the rock abrasion tool, a minimum of force must be used to push the tool onto the target. With the vehicle tilted 23.2 degrees, there was concern that applying too much force could cause the vehicle to lose traction on the slope and slide farther into the crater, possibly damaging the arm. Concerns were pacified when the rock abrasion tool operation worked flawlessly, abrading approximately 3 millimeters (about 0.12 inches) into the rock called "Cobble Hill."

Daily Update - 6/18/04
Diggin’ into ‘Tennessee’
Opportunity Status for sol 138-140

Opportunity spent sol 138 grinding an 8.12-millimeter (0.32 inch) hole into the rock target called "Tennessee." It took the rover 2 hours and 4 minutes to complete this grind, which is the deepest yet of the mission. After all this hard work, the rover went into a deep sleep for the night.

On sol 139, Opportunity used the microscopic imager to analyze the hole in Tennessee. The rover also performed both a daytime Moessbauer spectrometer observation and an overnight alpha particle X-ray spectrometer integration on the abraded surface.

Opportunity was busy finishing up some miniature thermal emission spectrometer observations of Tennessee on sol 140 and then began a long Moessbauer integration that ran for the entire sol. Opportunity enjoyed some more deep sleep after these activities and will finish up the last of the Tennessee observations the morning of sol 141.

Daily Update - 6/16/04
Spirit Reaches the 'Columbia Hills!'
Spirit Status for sol 156-158

On sol 156, Spirit roved 42 meters (138 feet) closer to a vantage point where it could observe the hill outcrops. Some of the images that Spirit sent back revealed a small and unusual rock that piqued scientists' interest and was informally named "End-of-Rainbow."

Part of the sol 157 plan was to observe End-of-Rainbow and use the alpha particle X-ray spectrometer, Moessbauer spectrometer and microscopic imager to study the "Shredded" soil target. However, the command load for sol 157 never made it to Spirit. Further analysis indicated that the problem had to do with the frequency drift associated with the colder temperatures on Mars as the planet moves into its southern winter season. This was an anticipated problem, and the rover team has already imposed some strategies that will help to prevent the problem in the future.

So, Spirit got a break on sol 157 and began sol 158 with nicely charged batteries. She executed the activities originally planned for sol 157, and then began to drive a bit closer to End-of-Rainbow. Although the direct path to End-of-Rainbow would be only a 4-meter (13 feet) drive, it was deemed too steep and hazardous by the rover team, so they planned a multi-stepped drive that could get the rover to the target safely. On sol 158, the first part of the drive was completed, putting Spirit a little farther away from the End-of-Rainbow target, but with a straight shot to the rock for sol 159.

Daily Update - 6/15/04
Exploring Endurance
Opportunity Status for sol 134-137

Opportunity is becoming accustomed to its new sloped home inside "Endurance Crater." There are positives and negatives to the rover’s new position and orientation. The solar array is oriented toward the northeast, which maximizes solar power in the morning and also warms the high gain antenna actuator faster, so heating is no longer required before the morning communications session. On the downside, the UHF communications sessions have degraded slightly at this orientation.

On sol 134, Opportunity drove 3.9 meters (about 13 feet) into Endurance Crater, then backed up 1.4 meters (4.6 feet), remaining inside the crater. Drive slippage and vehicle tilt was as predicted by the engineering team. An hour’s worth of remote sensing completed the sol. Opportunity then performed deep sleep overnight into the morning of sol 135.

On sol 135, Opportunity drove 1.3 meters (4.3 feet) deeper into Endurance Crater to a position that was about the deepest point it reached on sol 134. This short drive was intended to allow for detailed imaging of the first likely target for the instrument arm, a rock called "Tennessee." The drive went exactly as planned, leaving Opportunity with a final tilt of -19.44 degrees and a heading of 62.5 degrees. The rover then performed almost two hours of remote sensing, then set up for another night of deep sleep.

Sol 136 was spent performing a series of panoramic camera and miniature thermal emission spectrometer observations from sol 135’s final location. The miniature thermal emission spectrometer performed atmospheric measurements and an overnight observation during the early morning pass by NASA’s Mars Odyssey orbiter. Part one of a planned ingress (entry) survey campaign with the panoramic camera was initiated.

On sol 137, Opportunity approached the rock target referred to as Tennessee. Opportunity drove 1.19 meters (3.9 feet) deeper into Endurance Crater, placing Tennessee perfectly within the instrument arm’s reach. The rover is in position to perform the first series of arm operations starting on sol 139. Deep sleep mode was again invoked overnight from sol 137 to sol 138. The plans for the coming sols include grinding into Tennessee with the rock abrasion tool and investigating it with the rover’s spectrometers.

Total odometry after sol 137 is 1,466.16 meters (more than nine-tenths of a mile)!

Daily Update - 6/15/04
Are We There Yet?
Spirit Status for sol 152-155

On sol 152, Spirit continued its journey toward the "Columbia Hills" and completed an 83-meter (272 feet) drive that brought its total odometry to 3.2 kilometers (2 miles). After the drive, the rover completed some remote sensing that brought more details of the hills into view.

Spirit roved another 70 meters (230 feet) on sol 153, and 49 meters (161 feet) on sol 154. After the drive on sol 154, Spirit attained a miniature thermal emission spectrometer scan of the hills that will help scientists identify what the hills are made of.

As of sol l55, Spirit was roughly 50 meters (164 feet) from the base of the target location at the Columbia Hills. Spirit reached this location after a 23-meter (75 feet) drive that ended with the rover at a maximum tilt of 20 degrees. 20 degrees is well below the safe limit for tilt and was 3 to 4 degrees below the estimated tilt for this traverse.

Daily Update - 6/10/04
Opportunity Update
Opportunity Status for sol 123-127

On Opportunity’s 123rd sol the rover completed an alpha particle X-ray spectrometer activity and performed a Moessbauer spectrometer read on the target called "McDonnell." The rover also acquired microscopic images before repositioning to set up for instrument deployment device (arm) work on the target referred to as "Pyrrho." This interesting rock on the Endurance rim has a braided ripple pattern. After more remote sensing, Opportunity successfully went into "deep sleep" mode to conserve energy overnight and into the morning of sol 124.

Awakening from deep sleep on sol 124, Opportunity performed miniature thermal emission spectrometer activities, proving that the instrument was, once again, able to survive the cold martian night without its heater running. The rover also acquired 75 microscopic images and performed a Moessbauer integration on Pyrrho before executing another repositioning to put the target rock called "Diogenes" within the instrument arm’s work volume. This short drive was perfect and set the scene for rover planners to access nearly any point on this rock filled with intriguing disc-shaped cavities. Opportunity again took advantage of the deep sleep mode overnight into the morning of sol 125.

On Sol 125, the rover acquired 76 microscopic images on Diogenes. Very little else was done on this sol, as rover planners opted not to enter deep sleep in favor of waking up for the morning Mars Odyssey pass on Sol 126. Because it performed extensive instrument arm work and stayed awake for two Odyssey passes, the rover drained a fair amount from its battery.

Sol 126 was a very active sol, beginning with a quick placement of the Moessbauer instrument on Diogenes. The rover then napped for about two hours while the Moessbauer performed its integration. Upon waking, the rover stowed its arm and began a mobility test and preparation activity that will aid rover planners should they decide to traverse down steep rocky slopes in Endurance Crater. This set of activities included a draw-bar pull activity where the front rover wheels are locked and dragged back across rocks by driving the other four wheels backwards for about one meter (3.3 feet). The draw-bar pull is intended to give insight into the friction between the wheels and the rock surface at this site. The other mobility preparation activity was to scuff each wheel on the surface by driving one wheel at a time for a few rotations in each direction (with all the other wheels locked). This "pawing at the ground" activity was intended to scrub off the anodized layer on the surfaces of the wheels, which will allow for better grip. After these mobility activities, Opportunity traversed about 72 meters (236.2 feet) west around the crater towards "Karatepe." This very busy day also included relaying about 190 Megabits of data through Odyssey with two back-to-back afternoon passes. All this was made possible by having the option of deep sleep to save energy overnight, which Opportunity took full advantage of overnight into sol 127.

The plan for the coming sols involves approaching the rim of Endurance and imaging potential entry points to aid in the decision of whether or not to enter the crater.

Daily Update - 6/10/04
Opportunity Takes A Dip
Opportunity Status for sol 130-133

On sol 130 Opportunity traversed a total of about 45 meters (about 147.6 feet). About 39 meters (about 127.9 feet) of that was counter-clockwise along the edge of "Endurance Crater," and 6 meters (about 19.7 feet) toward the crater rim. The sol ended with the rover about 10 meters (32.8 feet) from the crater rim. The traverse ended up about 1 meter (about 3.3 feet) short of what was commanded due to a slightly uneven patch of ground that the rover seemed to run across near the end of the drive. Driving over this tripped a suspension limit that rover planners had set to help prevent inadvertently driving into difficult terrain. Deep sleep was again invoked for the night of sol 130 to 131.

On sol 131 the rover successfully traversed up the slope to the crater edge, took a detailed set of images and then backed off a little to optimize its orientation for the rover’s communications passes. These images will aid in the project’s assessment of traversing on the interior slopes of Endurance Crater in this vicinity. Deep sleep was not invoked on this night, in favor of relaying data to Mars Odyssey in the early morning on sol 132.

On sol 132 the rover re-approached the crater rim at the location and orientation most advantageous for the "pre-dip" into the crater. This approach was designed to just crest the edge of the crater and leave the rover roughly level (with the front two wheels in the crater). The drive executed beautifully.

On sol 133 the rover executed the first real "dip" into Endurance Crater. The intent was to go far enough in that all wheels would be on the slope of the crater, and then come all the way back out, proving that the rover was capable of getting back out before going very deep. The other main objective was to gather information on the degree and nature of any slip that would be experienced while traversing the crater wall. The execution went extremely well, with slips and disturbance of the terrain well below acceptable levels, giving the team confidence that the rover is capable of going deeper. The engineering team will continue to characterize the variety of slopes and materials that Opportunity will encounter deeper in the crater.

Daily Update - 6/10/04
To Ingress or Not to Ingress
Opportunity Status for sol 127-129

Engineers and scientists on the Mars Exploration Rover project continue to contemplate the safety and viability of a trek into "Endurance Crater."

After a "deep sleep" overnight, Opportunity began its 127th sol with a three and one-half hour nap. Upon awaking, the rover drove 50 meters (164 feet) on a directed drive, turned to face Endurance Crater and took images using its front hazard-avoidance cameras. Opportunity then performed 45 minutes of remote sensing using the panoramic camera and miniature thermal emission spectrometer. The rover then supported an afternoon and overnight Mars Odyssey data pass.

Foregoing deep sleep over the sol 127 night, sol 128 was spent approaching the crater rim. The drive took about 10 minutes and moved Opportunity 13.4 meters (44 feet), coming to rest about 5 meters (16.4 feet) from the lip of the crater. The remainder of the day was spent supporting two afternoon Odyssey passes. The rover then underwent its sixth deep sleep cycle into the morning of sol 129.

On sol 129, it was decided that Opportunity was not in the most advantageous location for entering the crater. The rover was commanded to move approximately 50 meters (164 feet) back along the crater rim, close to the rock called "Lion Stone." After a 4.5-meter (14.7 feet) bump toward the rim and some navigation and hazard-avoidance camera images, the rover backed up 4.5 meters (14.8 feet) and then drove 8 meters (26.2 feet) toward Lion Stone. Power limited the total drive duration. Instead of utilizing the deep sleep mode overnight into sol 130, Opportunity again supported two Odyssey passes that returned a large volume of data to Earth.

After sol 129, Opportunity’s odometer read 1,395.91 meters (4,579.76 feet).

Sols 130 and beyond will see Opportunity drive farther toward the possible point of ingress (entry).

Daily Update - 6/9/04
Spirit Surpasses 3 Kilometer Mark!
Spirit Status for sol 148-151

During sols 148 through 151, Spirit advanced significantly closer to the "Columbia Hills" and now sits only 220 meters (722 feet) from its first target at the base, a location informally named "Spur B."

Sol 148 was a driving sol, with Spirit completing a 64.7-meter (212.3 feet) engineer-directed drive. This put the rover in position for some sol 149 work with the robotic arm, and provided a great view of the Columbia Hills

On Sol 149, Spirit took a break from driving and surveyed the Columbia Hills with the panoramic camera and mini thermal emissions spectrometer. After that, the rover attained an alpha particle X-ray spectrometer observation of the filter magnet and capture magnet. Spirit takes a look at its magnets every now and then to assess what magnetically susceptible materials have accumulated. The last magnet check was on sol 92.

Spirit used its alpha particle X-ray spectrometer and Moessbauer spectrometer to observe a rock called "Joshua" on sol 150. Unfortunately, the rest of the sol's planned work with the instrument deployment device did not take place because of a command anomaly, which made Spirit think that a collision between the rock abrasion tool and the forearm might occur. Therefore, the tool change and all subsequent arm motions were prevented for the rest of the sol.

Spirit was back to business on sol 151, and finished observing Joshua and the science magnets with the tools on the instrument deployment device. After that, the rover was off, and successfully completed a 73-meter (240 feet) drive toward the Columbia Hills.

Daily Update - 6/8/04
Keep On Rovin’
Spirit Status for sol 145-147

On sol 145, Spirit completed a 43-meter (141 feet) engineer-directed drive and then spent two hours roving another 55 meters (180 feet) using the autonomous navigation software.

Spirit roved 61 meters (200 feet) on sol 146, and 52 meters (171 feet) on sol 147. At its current rate, the rover is on schedule for a sol 160 arrival at the base of the "Columbia Hills."

Spirit currently has a total of 2.98 kilometers (1.85 miles) on its odometer.

Daily Update - 6/3/04
Roving Toward the Hills
Spirit Status for sol 143-144

Spirit began sol 143 using the panoramic camera to image its surroundings. After a restful nap, the rover began driving and advanced 69 meters (226.4 feet) in an engineer-directed drive toward the "Columbia Hills." After doing some mid-drive science imaging, Spirit attempted additional driving using its autonomous navigation software, but detected hazards in the immediate vicinity of the rover and therefore covered no additional ground.

On sol 144, Spirit covered 24.4 meters (80 feet) in another engineer-directed drive. Once again, the terrain was too rough to permit further driving beyond this point using the autonomous navigation software. On sol 145, Spirit will continue driving in its quest for the hills.

Daily Update - 6/2/04
Spirit Recovers from a Low Probability Software Error
Spirit Status for sol 136-139

Spirit had plans to spend sols 136 through 139 observing its surroundings with the remote sensing instruments on its mast, and then exploring the trench it dug on sol 135 with the instruments on the robotic arm. However, an anomaly on sol 136 restricted the rover's activity, allowing Spirit to achieve only remote science objectives during the four-sol segment. Spirit has since fully recovered and has resumed normal science operations. On sol 136, engineers sent Spirit its commands and received the beep confirming that they were running. However, the afternoon pass by NASA’s Mars Odyssey orbiter did not provide any data, and the orbiter reported that it had not heard from Spirit's UHF antenna. Engineers first thought was that the signal might have been blocked by the "Columbia Hills" because of the low elevation pass of Odyssey. The telecommunications team disagreed with this hypothesis and thought something might be wrong. Scientists and engineers would have to wait until the afternoon of sol 137 for their next communications opportunity.

During sols 136 and 137, engineers executed a number of communication trials with Spirit, but did not receive any telemetry from the rover, or have any indication of what had gone wrong until finally data came back from a sol 137 afternoon pass by NASA’s Mars Global Surveyor. That pass revealed that on sol 136, Spirit's software had experienced an extremely low probability error that rebooted the computer and terminated all the sequences. This error created a domino effect of communication difficulties and explained why engineers had not been able to make contact with the rover. All the anomaly events are understood.

Sol 138 was spent recovering the state of the rover, including reestablishing a master sequence, restoring high-gain antenna communications, and reinitializing the panoramic camera mast actuators whose positions had been marked as unknown.

On sol 139, Spirit performed the remote-sensing observations that had been lost along with some observations coordinated with Mars Global Surveyor that had been planned for sol 138. All activities on sol 139 completed successfully, which verified that Spirit had returned to normal science operations.

Engineers have developed a way to reduce even further the probability of encountering this particular error again and reported that on the bright side, Spirit was able to fully charge its batteries during the anomaly.

Sol 140 picked up with the original plan for Sol 137, performing in-situ work in the trench.

Daily Update - 6/2/04
Back to Business
Spirit Status for sol 140-142

Spirit spent most of sol 140 investigating the trench it dug on sol 135. It got an up-close look at the trench with the microscopic imager and then began a five-and-a-half hour integration with the Moessbauer spectrometer. Doing double duty, Spirit surveyed the "Columbia Hills" with the panoramic camera and miniature thermal emission spectrometer during the Moessbauer observation. Following the afternoon Odyssey communications window, Spirit changed tools and began an overnight integration on two targets with the alpha particle X-ray spectrometer.

On sol 141, Spirit continued to observe the trench with the Moessbauer spectrometer and microscopic imager. The rover also obtained panoramic camera images of its surroundings while doing work with the robotic arm. It then stowed the instrument deployment device and backed up 0.85 meters (2.8 feet). Spirit spent most of the afternoon observing the trench using the miniature thermal emission spectrometer.

Spirit got a chance to stretch its wheels and do some driving on sol 142, but before taking off, the rover finished the trench observations with some panoramic camera imaging. Then it was time to rove. Spirit completed a 30-minute, engineer-directed drive and then turned the wheel over to the autonomous navigation software for another hour and 15 minutes of driving. Spirit roved a total of 61 meters (200.1 feet) closer toward the Columbia Hills.

Spirit has 2,647.7 meters (1.65 miles) on its odometer, and just over 620 meters (.4 miles) to rove before reaching the base of the Columbia Hills.