Sol details:
Sol 238
Opportunity completed instrument arm operations on a soil target called "Auk" by finishing a multi-sol Mössbauer spectrometer integration and collecting microscopic images of undisturbed soil. It then performing remote sensing observations on the next target, a rock called "Ellesmere." Once the morning activities were complete, Opportunity took a 90-minute nap then stowed the arm and drove backwards 0.34 meters (1.1 feet). The rover used an afternoon communications session on sol 238 and an early morning session on sol 239.

Sols 239 and 240
The planning session for sols 239 and 240 was extremely challenging for the uplink team. As the rover project transitions to five-day-a-week planning, the Opportunity team planned two sols of activities to be uplinked on sol 239. Adding to the complexity, the two sols' activities included difficult instrument arm placement activities. Rover planners rose to the occasion. The sol started with 45 minutes of microscopic imaging, then placement of the alpha particle X-ray spectrometer on a target area of Ellesmere called "No Coating." Opportunity performed a couple hours of remote sensing, used an afternoon communications session and then went into overnight deep sleep. On sol 240, Opportunity began taking a reading with the alpha particle X-ray spectrometer at 7:00 local solar time, then went back to sleep. After waking, it did an hour of remote sensing observations, completed the alpha particle X-ray spectrometer integration and collected more microscopic imager pictures. The rover then placed the alpha particle X-ray spectrometer on its next target, "Barbeau." Another hour of remote sensing completed the sol.

Sol 241
Opportunity finished its alpha particle X-ray spectrometer integration on Barbeau, collected more microscopic images, switched tools to the Mössbauer spectrometer and started that integration. The rover performed a mini deep sleep overnight. Sol 241 ended on Sept. 27.

Total odometry after sol 241 is 1,573.83 meters (0.98 miles - almost to the 1-mile mark).

Daily Update - 9/29/04
Spirit back to normal operations
Spirit Status for sol 243-262

Spirit has successfully transitioned back to normal operations from conjunction operations, when Mars and Earth were on opposite sides of the Sun. During conjunction (sols 244 through 255), engineers and scientists did not attempt normal operations due to the low probability of successful communications. From sols 244 to 249, the rover team did transmit several "no operation" commands to test the communications link. On Spirit's sol 249, Opportunity experienced an unexpected software reset, apparently triggered by a corrupted "no operation" command. As a result of that problem, engineers ceased all commanding on Spirit from sol 250 until sol 256, at which time the likelihood of receiving corrupted commands was once again very low.

From sols 244 through 255, pre-loaded sequences performed daily science, which included atmospheric studies (using the miniature thermal emission spectrometer and the panoramic camera) and Moessbauer spectrometer integration on the filter magnet, which is one of two dust-collecting magnets on Spirit's main deck. Spirit relayed data to the Mars Odyssey orbiter every afternoon throughout conjunction. Odyssey in turn attempted to relay that data back to Earth with limited success due to solar conjunction. As a result of the difficulties getting data off of the rover, the memory available for science data storage shrunk to roughly 100 megabits by sol 261, but has recovered as of sol 262 to roughly 400 megabits.

Sol highlights:
Sol 243 was the last sol of normal commanding for Spirit before conjunction. The rover team successfully re-transmitted four conjunction sequences that had not made it on-board during the sol 242 uplink. The team saw no transmission errors (but commanded everything twice just in case), and the rovers performed the commanded remote sensing science.

On sol 244, the rover team transitioned into conjunction operations and did the first "no-op" commanding tests during midday to see how effective the command link was as Mars moved further behind the Sun. The team received data from the Odyssey orbiter indicating that Spirit was healthy and proceeding normally with on-board conjunction sequences.

Sols 245 through 255 were the solar conjunction quiet period. No commanding was done. Spirit automatically took daily atmospheric science measurements and made filter magnet observations with the Moessbauer spectrometer.

During sols 256 through 257, Spirit took 48 more hours of Moessbauer observations on the filter magnet. A dirt clod from a previous Moessbauer soil touch was inadvertently placed on the perimeter of the filter magnet on sol 240. As a result, engineers believed this could have been the rover team's last best chance to collect Moessbauer data on the uncontaminated dust sample from that magnet. This is because when the Moessbauer instrument was removed, there was a chance that dirt from the clod would sprinkle or spread to the center area of the magnet.

On sol 258, the team removed the Moessbauer instrument from the filter magnet and took microscopic images of the both magnets. From the image thumbnails, the team could see that some dirt from the clod was indeed deposited on the outer area of the filter magnet. Front hazard-avoidance camera images taken after the Moessbauer spectrometer was removed clearly showed dirt still attached to the Moessbauer contact plate.

After finishing with the magnets, engineers moved the rover arm back down to the soil, to the same spot that had been touched by the Moessbauer instrument on sol 240. The rover team then repeated a microscopic imager sequence of that soil to see if winds had deposited anything there during conjunction. The team then centered the alpha particle X-ray spectrometer on the same soil and started an integration later that night.

On sol 259, Spirit changed tools to the Moessbauer spectrometer and started a 24-hour integration on the same disturbed soil spot. Spirit also started a three-sol thermal investigation, using panoramic camera and miniature thermal emission spectrometer observations of soil targets several times during each sol.

On sol 260, Spirit completed the Moessbauer integration of the disturbed soil.

On sol 261, Spirit stowed its arm then drove backwards 1.5 meters (4.9 feet) to take post-conjunction panoramic camera pictures of the soil underneath the rover as part of the conjunction wind experiment. Spirit also took navigation camera images of the road ahead in preparation for future drives.

On sol 262, due to the limited amount of available science data storage, planned activities were limited to a Moessbauer spectrometer integration on a rock, limited remote sensing, and routine atmospheric observations. That plan did not make it on board due to a problem during the communications uplink session. The deep space network antenna was pointed a few degrees below its lower safety limit when the transmitter was supposed to turn on, causing an interlock mechanism to turn off the transmitter. By the time the antenna was reconfigured, not enough time remained to get the full sequence load transmitted. Fortunately, one sequence did make it to the rover and was successfully executed, freeing up roughly 250 megabits of memory for future sols. Sol 262 ended on Sept. 28.

Daily Update - 9/13/04
Spectrometers Sample Clean and Dirty Targets
Opportunity Status for sol 215-217

On sol 215 Opportunity completed a reading with its Moessbauer spectrometer of a target called "Kirchner," where a wire brush on the rover's rock abrasion tool had scrubbed a circular patch on the surface of a rock called "Escher." The rover also made some remote-sensing observations then then set up for using its alpha particle X-ray spectrometer on Kirchner early the following morning. However, an image from the rover's hazard-avoidance camera revealed that the doors of the alpha particle X-ray spectrometer had not completely opened. The door is a tricky mechanism; incomplete openings and closings have occurred before, and the team continues to work on approaches to more reliably maneuver the door.

On sol 216 the rover successfully acquired early morning alpha particle X-ray spectrometer data on Kirchner. Despite the incomplete opening of the instrument's dust doors, the spectra look good. No repeat of the integration will be necessary. The rover also used the Moessbauer spectrometer to examine another brushed target, "EmilNolde," on Escher. This reading was planned to run into the evening then later, following a deep sleep, to resume in the early morning of sol 217. The Moessbauer placement went fine. The rover was commanded to close and reopen the alpha particle X-ray spectrometer doors and this went well. The doors are now properly open and ready for action on sol 217.

On sol 217, which ended on Sept. 3, Opportunity used its rock abrasion tool to brush a target called "Otto Dix," and used its microscopic imager to look at the brushed area. Then the rover was commanded to place the alpha particle X-ray spectrometer on EmilNolde, precisely on a "dirty" portion of that target (an area that was not very well cleared away by the brush action a few sols ago). The plan was to collect data with the alpha particle X-ray spectrometer in the evening, perform a move in the middle of the night to a cleanly brushed portion of EmilNolde and integrate again until morning. These two integrations will be used to discern the differences between the "clean" and "dirty" portions of the target. A 100-megabit afternoon downlink through Mars Odyssey on sol 217 showed that all activities went well through the placement of the alpha particle X-ray spectrometer on the "dirty" part of EmilNolde.

Daily Update - 9/9/04
Spirit on Autopilot
Spirit Status for sol 239-242

Spirit is in safe place to continue daily science observations automatically throughout the solar conjunction period when engineers and scientists will be unable to send commands reliably to the rover. An 18-day period began a transition into solar conjunction on sol 241, when the Sun partially obscured the communications path between Earth and Mars, making communications sessions unreliable. Engineers were able to successfully command Spirit on sol 241, and they had partial commanding success on sol 242.

Engineers will attempt to command Spirit on sol 243 also. From sol 244 through sol 255, sequences already safely on board will perform a set of science activities on a daily basis. On sols 256 through 258, the last three days of conjunction, the rover team will attempt normal operations again.

On sol 242, engineers sent Spirit a set of coordinated commands to use the miniature thermal emission spectrometer and panoramic camera for observations of possible future science targets. A new set of 12 conjunction master sequences was also transmitted successfully to Spirit. This new set of conjunction master sequences will use less energy than previous sequences.

For the conjunction period, the rover team has placed the Moessbauer spectrometer on one of the two magnets on the rover deck. Spirit will activate the Moessbauer instrument every day during conjunction in order to characterize the dust that has collected on the magnet. However, a wrinkle has developed in this plan. Before placing the Moessbauer spectrometer on the magnet, Spirit placed it on the soil in front of its current location. That soil touch was done to leave a soil impression that would be studied after conjunction for changes. Images taken after the touch indicate that Spirit inadvertently picked up some soil and likely sandwiched that soil onto the magnet with the Moessbauer. It's the team's first inadvertent sample acquisition!

Engineers and scientists decided to leave the Moessbauer in place on the magnet and will evaluate the status and effect of the dirt clod after conjunction. The dirt does not pose any threat to the rover from an engineering perspective.

Since Spirit arrived at its solar-conjunction resting place, its science activities have focused on gathering data from the surrounding area for use in planning post-conjunction sols. Navigation camera images in Spirit's drive direction have been used to develop traverse maps. These maps show areas that allow Spirit to maintain a north-facing tilt; these areas will provide significantly more solar energy and will therefore be favored as the team plans the traverse to Spirit's next science target.

During conjunction, Spirit will transmit five-minute "beep" tones, and engineers will send "No-operation" commands to the rover to characterize effects that the conjunction has on radio transmissions between Mars and Earth.

Daily Update - 9/9/04
RAT is Rearin' to Go!
Opportunity Status for sol 211-214

Opportunity is healthy and continuing to explore a rock called "Escher" on the southwestern slope of "Endurance Crater."

Sol 211: Opportunity awoke from deep sleep at 7 a.m. local solar time. It re-enabled survival heaters on its miniature thermal emission spectrometer and re-started a Moessbauer spectrometer examination of a target called "Kirchner." The rover made observations with its panoramic camera and its miniature thermal emission spectrometer from about 11 a.m. to 2 p.m. local solar time, focusing on getting thermal inertia measurement of the dunes at different times of day. A planned tool change to the alpha particle X-ray spectrometer in the afternoon failed due to a sequencing error in retracting the Moessbauer spectrometer from the surface. A conditional sequencing check prevented the overnight alpha particle X-ray spectrometer integration from occurring as desired in such fault cases.

Sol 212: A calibration of the rock abrasion tool calibration was completed successfully. The tool is healthy and ready for action! An aggressive plan acquired 80 microscopic images of the rock Escher. As part of the team's efforts to increase operational flexibility, a test was conducted involving operating the miniature thermal emission spectrometer in parallel with arm operations. Unfortunately, this resulted in some corrupted data from the miniature thermal emission spectrometer due to vibrations as the rover arm moved. The rover used its Moessbauer spectrometer in the afternoon before going into deep sleep overnight.

Sol 213: Opportunity awoke from deep sleep and re-started the Moessbauer integration. The rover performed some remote sensing during the day and then changed tools to the alpha particle X-ray spectrometer for an overnight integration. Later it completed a midnight thermal inertia observation with the miniature thermal emission spectrometer, which required an hour of actuator preheating.

Sol 214: Opportunity completed the alpha particle X-ray spectrometer observation and successfully used the rock abrasion tool to brush clean two targets on Escher ("EmilNolde" and "Kirchner_RAT"). Then it made observations with its microscopic imager, hazard-avoidance camera and panoramic camera. The Moessbauer spectrometer was then positioned on Kirchner_RAT, where it analyzed the rock's mineral composition until the rover went into deep sleep overnight. Sol 214 ended on Aug. 31.

Daily Update - 9/7/04
Spirit finishes observing 'Ebenezer' and moves on to 'Tikal'
Spirit Status for sol 232-238

Spirit found a comfortable location on a rock outcrop and spent cold autumn days performing observations of a rock called "Ebenezer" with the rover's science instruments. Spirit finished observations of Ebenezer and moved over to the next location, "Tikal," about nine meters (30 feet) away. Spirit will spend solar conjunction at Tikal. Solar conjunction is when Earth and Mars are on opposite sides of the Sun. Due the interference with the Sun, communications between Earth and the spacecraft at Mars will be minimal during solar conjunction, which occurs during Spirit's sols 244 through 255.

On sol 232, Spirit completed an overnight reading with its alpha particle X-ray spectrometer on a target dubbed "Cratchit 2," where the rover had earlier used its rock abraision tool to cut a hole exposing the rock's interior. Spirit took images of the same target with the microscopic imager. Spirit then placed the Moessbauer spectrometer on Cratchit 2 and started a very long, two-sol integration.

After the two-sol Moessbauer spectrometer activity, Spirit spent sol 234 performing 90 minutes of remote sensing. On sol 235, Spirit changed tools from the Moessbauer spectrometer to the microscopic imager and took pictures. Then Spirit used the alpha particle X-ray spectrometer for thirty minutes. After completing the alpha particle X-ray spectrometer reading, the arm was stowed so that on sol 236 the rock abrasion tool brushings could be imaged using the panoramic camera without the arm blocking any part of the image.

Spirit spent sols 236 to 238 brushing eight adjoining patches on Ebenezer to create a large enough scrubbed area for analyzing with the miniature thermal emission spectrometer, then drove up to the rover's designated vacation spot for solar conjunction.

Spirit bumped backwards on sol 237, and took some navigation camera images of the brushed area of Ebenezer to support miniature thermal emission spectrometer observations on the next sol. A navigation camera panorama was taken in the expected drive direction, toward Tikal.

In the morning of sol 238, the panoramic camera imaged the brushed area of Ebenezer. A little after noon, the miniature thermal emission spectrometer took spectral readings of both the brushed area and a hole that rock abrasion tool hole had cut into Ebenezer on sol 231. At 2 p.m. Gusev time, Spirit took an afternoon drive to Tikal, about nine meters (30 feet) away.

Daily Update - 9/1/04
'Look Mom, no pebble!'
Opportunity Status for sol 209-210

Sol 209 activities for Opportunity focused on recharging its batteries and downlinking data through both an afternoon communications link with NASA's Mars Odyssey orbiter and an overnight Odyssey pass (early morning sol 210). The rover also made some remote sensing observations. The sol 209 plan was constructed without benefit of the sol 208 downlink (due to the restricted nature of the planning at this point in the cycle of Mars days progressing relative to Earth days). For that reason, activities were limited to remote sensing, which did not depend upon knowledge of the exact position of the rover. All went fine, and about 165 megabits of data were returned through relay by Odyssey.

On sol 210, which ended on Aug. 27, the rover was commanded to image the rock abrasion tool in a variety of positions to get better knowledge of a pebble that appeared to be jammed between rotors in an earlier image. Then the rover used its microscopic imager to survey several spots on a rock called "Escher." In addition, it took panoramic camera images for assembling into a mosaic of the dune field at the bottom of "Endurance Crater." The diagnostic images of the rock abrasion tool brought good news with the revelation that there is no longer a pebble jammed between the grind bits! Apparently, sometime after the last previous images of the tool were acquired on sol 200, the pebble fell out, perhaps due to thermal cycling or vehicle motion. The team will proceed next with diagnostic actions to confirm that the abrasion tool is functioning normally again. Those activities are planned for sol 212.