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M I S S I O N     M A N A G E R S   
Scott Lever, Mission manager Mike Seibert, Mission manager Al Herrera, Mission manager
Scott Lever Mike Seibert Al Herrera
P R E V I O U S    M I S S I O N    M A N A G E R S
Matt Keuneke, Mission Manager Cindy Oda, Mission Manager Rich Morris, Mission Manager Bill Nelson, Mission manager
Matt Keuneke Cindy Oda Richard Morris Bill Nelson
Byron Jones, Mission Manager Mark Adler, Mission Manager Leo Bister, Mission manager Beth Dewell, Mission Manager
Byron Jones Mark Adler Leo Bister Beth Dewell
Emily Eelkema, Mission Manager Jeff Favretto, Mission Manager Soina Ghandchi, Mission Manager Andy Mishkin, Mission Manager
Emily Eelkema Jeff Favretto Saina Ghandchi Andy Mishkin
Art Thompson, Mission Manager Rick Welch, Mission Manager Colette Lohr, Mission Manager Dan Gaines, Mission Manager
Art Thompson Rick Welch Colette Lohr Dan Gaines

sols 2125-2130, December 25-30, 2009: Minimal Progress in Recent Extraction Drives

Spirit remains embedded at the location called "Troy" on the west side of Home Plate. Attempts to extricate Spirit have been complicated by the loss of functionality in the right-rear wheel and the lack of meaningful functionality with the right-front wheel.

On Sol 2126 (Dec. 26, 2009), an extrication drive was commanded with all six wheels, although performance was not expected from the right-front and right-rear wheels. Spirit was commanded forward in five steps of 10 meters (33 feet) of wheel rotation each. The rover stopped during the fifth step when excessive rover sinkage was detected. Little forward progress was achieved.

On Sol 2130 (Dec. 30, 2009), a different drive strategy was commanded where the wheels were steered back and forth before forward motion was commanded. However, the activity stopped when one wheel encountered excessive resistance while turning, likely a result of the buried state of the wheels. The plan ahead is to straighten the wheels and proceed with a forward extrication drive.

As of Sol 2130 (Dec. 30, 2009), Spirit's solar-array energy production was 260 watt-hours, with an atmospheric opacity (tau) of 0.480 and a dust factor of 0.557. Total odometry was 7,730.04 meters (4.80 miles).


sols 2118-2124, December 17-24, 2009: Intermittent Functionality in Right-Front Wheel

Spirit remains embedded in the location called "Troy" on the west side of Home Plate.

The right-side wheels were tested on Sol 2118 (Dec. 17, 2009) before that sol's drive. The tests show the right-front wheel has intermittent and limited functionality. The right-rear wheel remains non-functional. The drive completed only the first of four steps and produced barely perceptible movement forward.

A drive on Sol 2120 (Dec. 19, 2009), intended to gather wheel performance data, produced no apparent progress but showed the left bogie angle increasing. This suggested the left-middle wheel was being lifted into the air. Efforts to "flatten" the suspension system on Sol 2122 (Dec. 22, 2009) proved counterproductive, with wheels digging into the soil instead of pulling laterally.

A further drive for Sol 2126 (Dec. 26, 2009) was planned using different speeds on different wheels to try to "flatten" the suspension system and improve traction on the left middle wheel.

The anomalous voltages first seen on the single-point ground on Sol 2104 (Dec. 3, 2009) have persisted and are likely permanent.

As of Sol 2124 (Dec. 24, 2009), Spirit's solar-array energy production was 270 watt-hours, with an atmospheric opacity (tau) of 0.450 and a dust factor of 0.544. Total odometry is 7,730.01 meters (4.80 miles).


sols 2111-2117, December 10-16, 2009: Surprise from Right-Front Wheel

Spirit remains embedded in the location called "Troy" on the west side of Home Plate. Because of continuing problems with the right-rear wheel, a test of the right-front wheel was done on Sol 2113 (Dec. 12, 2009) to gain insight into the signature for a failed wheel. The right-front wheel had become inoperable back on Sol 779 (March 13, 2006). Surprisingly, the right-front wheel indicated normal motor continuity.

The project also discovered a change in what is known as the single-point ground. A negative voltage is present where no voltage should be. This suggests some sort of electrical short to the rover chassis. The behavior of this single-point ground correlates with the onset of problems with the right-rear wheel and with usage of any of the mobility actuators. This suggests that the rover's motor controller board is suspect.

The right wheels were tested again and driven as part of an extrication maneuver on Sol 2117 (Dec. 16, 2009). The right-front wheel functioned normally for the first three steps of the drive and stopped working during the last step, completing about 10 wheel revolutions. The right-rear wheel did not move at all. The rover only moved slightly during this drive. The project is continuing the investigation of these electric and wheel problems and continuing to explore the functionality of the right-front wheel.

As of Sol 2117 (Dec. 16, 2009), Spirit's solar-array energy production is down ro 277 watt-hours, with an atmospheric opacity (tau) of 0.503 and a dust factor of 0.557. Total odometry is 7,730.01 meters (4.80 miles).


sols 2100-2110, November 29 - December 9, 2009: Trouble with Right-Rear Wheel

Spirit remains embedded in the location called "Troy" on the west side of Home Plate.

Diagnostic tests from Sol 2109 (Dec. 8, 2009) on Spirit's right-rear wheel indicate a troubled wheel. The right-rear wheel rotor resistance tests continue to show very elevated resistance. No motion of the right-rear wheel occurred during a backward commanded motion test. The rotor resistances on all the other operating wheels are nominal.

The plan ahead includes more rotor resistance tests, application of higher voltage to the right-rear wheel to see if any movement will occur, and a check of the right-front wheel to confirm its status and to see if it may offer insight into the right-rear wheel's condition.

As of Sol 2110 (Dec. 9, 2009), Spirit's solar-array energy production is 298 watt-hours, with an atmospheric opacity (tau) of 0.517 and a dust factor of 0.563. Total odometry is 7,730.00 meters (4.80 miles).


sols 2096-2099, November 25-28, 2009: Diagnostic Wheel Tests Continue

Spirit's extrication from her embedded location at Troy on the west side of Home Plate has been complicated by a recurring stall condition with the right rear wheel.

After diagnostic tests on Sol 2095 (Nov. 24, 2009), indicated a freely moving wheel, another two-step drive with 5 meters (16 feet) of wheel spin was commanded on Sol 2099 (Nov. 28, 2009). That drive resulted in another right rear wheel stall after only 1.4 meters (5 feet) of wheel motion. Analysis of a right rear wheel stall back on Sol 1837 (March 25, 2009), well before embedding, suggests that the stall may not be terrain related, but could be internal to the wheel motor and gearbox. To investigate this, three sets of rotor resistance tests at cold, ambient and warm temperatures were commanded over Sols 2104 (Dec. 3, 2009), and 2105 (Dec. 4, 2009), to check the health of the motor windings and motor brushes. A small right rear wheel motion in the direction of the stall was also commanded on Sol 2104 to see if the stall persists.

The results of these diagnostic tests should be known later tonight (Thursday) and Friday with analyses performed on Friday and over the weekend. The next drive for Spirit would be no sooner than Monday (Dec. 7, 2009).

As of Sol 2099 (Nov. 28, 2009), the rover solar array energy production was 316 watt-hours with an atmospheric opacity (tau) of 0.572 and a dust factor of 0.567. Total odometry is 7,730.00 meters (4.80 miles).


sols 2091-2095, November 20-24, 2009: Extrication Attempt Continues

The Spirit team is continuing with the process of attempting to extract her from her embedded location at Troy on the west side of Home Plate.

On Sol 2092 (Nov. 21, 2009), a two-step 5-meter (16 feet) forward motion was commanded. After the rover completed about 4 meters (13 feet) of wheel spin, a stall occurred in the right-rear wheel. Telemetry suggested that the wheel was bogging down.

On Sol 2095 (Nov. 24, 2009), a series of diagnostic tests on the right-rear wheel was commanded. The test results indicated a fully functioning right-rear wheel free of obstruction. As part of the diagnostics, a short (1.5 meter) forward drive of the rover was commanded. The rover moved forward about 2 millimeters (0.08 inch). The plan ahead is to continue with extrication. Another 5-meter (16 feet) two-step drive is planned for the Thanksgiving holiday weekend.

As of Sol 2095 (Nov. 24, 2009), the rover solar array energy production was 325 watt-hours, with an atmospheric opacity (tau) of 0.590 and a dust factor of 0.575. Total odometry is 7,730.00 meters (4.80 miles).


sols 2084-2090, November 13-19, 2009: Extrication Attempt Begins

Spirit has begun her long-awaited extrication process.

The first commanded motion was on Sol 2088 (November 17, 2009). Two straight forward steps of 2.5 meters (8.2 feet) each were sequenced. However, due to a hair-trigger limit on the rover tilt, the drive stopped as soon as it began and no discernable motion in the rover was observed.

With improved value for the rover tilt, the same two-step motion was sequenced on Sol 2090 (Nov. 19, 2009). Spirit successfully completed the first step of the planned motion. The second step was not performed because Spirit exceeded the 1-centimeter (0.4-inch) three-dimensional distance limit that was imposed in the plan. The center of the rover moved approximately 12 millimeters (0.5 inch) forward, 7 millimeters (0.3 inch) to the left and about 4 millimeters (0.2 inch) down. The rover tilt changed by around 0.1 degree. Small forward motion was observed with the non-operable right-front wheel. The left-front wheel showed indications of climbing.

It is cautioned that these motions are too small to establish any trends at this time. The plan ahead is to continue forward driving once all the necessary analysis is complete and reviewed.

As of Sol 2090 (Nov. 19, 2009), Spirit's solar-array energy production is 346 watt-hours, with an atmospheric opacity (tau) of 0.517 and a dust factor of 0.588. Total odometry is 7,729.97 meters (4.80 miles).


sols 2077-2083, November 5-11, 2009: Flash Memory in Use Again

Spirit is preparing to attempt extrication from her embedded location at "Troy" on the west side of "Home Plate."

The project was successful in reformatting Spirit's on-board flash memory file system on Sol 2083 (Nov. 11, 2009). The rover is now again using the non-volatile flash file system for telemetry storage.

On Sol 2078 (Nov. 6, 2009), Spirit straightened her wheels in preparation for the first straight-ahead extrication drive, currently planned for Sol 2088 (Nov. 17, 2009). Spirit also collected another microscopic imager (MI) mosaic of the rover underbelly on Sol 2081 (Nov. 9, 2009).

As of Sol 2082 (Nov. 10, 2009), Spirit's solar-array energy production was 368 watt-hours, with an atmospheric opacity (tau) of 0.569 and a dust factor of 0.5995. Total odometry remains at 7,729.97 meters (4.80 miles).


sols 2070-2076, October 29 - November 4, 2009: Dealing with Flash Access

Spirit is still suffering from the inability to access the on-board, non-volatile (flash) memory file system. However, the operations team has developed a strategy to allow science activities to continue.

To ensure that science data collected by Spirit is returned to Earth, the team has been keeping Spirit awake each sol from the morning communication session through the data relay via the Odyssey orbiter. (Data stored in volatile, random-access memory is not retained when the rover powers down for energy-conserving sleep.)

The engineering team has determined that reformatting the file system portion of flash memory will restore the use of the flash memory for data storage. The Flash file system has been formatted once before on Spirit on Sol 32. This was part of the recovery from the anomaly experienced on Sol 18. The project intends to re-format the Flash file system shortly.

As of Sol 2076 (Nov. 4, 2009), Spirit's solar-array energy production is 359 watt-hours, with an atmospheric opacity (tau) of 0.599 and a dust factor of 0.633. Total odometry remains at 7,729.97 meters (4.80 miles).


sols 2063-2069, October 22-28, 2009: Amnesia-like Symptoms Return

Spirit has experienced another complication. On Sol 2065 (Oct. 24, 2009), Spirit experienced a reset event and a problem with mounting its non-volatile flash memory. The rover resumed activities without using its flash memory, instead using its volatile random-access memory (RAM) to store telemetry. When the rover goes to sleep, telemetry stored only in RAM is lost. The project has instructed the rover to stay awake until its afternoon relay pass with Mars Odyssey to return the day's data before napping.

The project is planning to reformat the rover's flash memory file system to restore it to normal operation. Spirit is otherwise in good health.

As of Sol 2069 (Oct. 28, 2009), Spirit's solar-array energy production was 411 watt-hours. On Sol 2064 (Oct. 23, 2009), atmospheric opacity (tau) was 0.599. Total odometry remains at 7,729.97 meters (4.80 miles).


sols 2056-2062, October 15-21, 2009: Antenna Back to Normal Use

Spirit has recovered from X-band fault and is using her steerable high-gain antenna (HGA) normally.

The clearing of the X-band fault was to occur on Sol 2056 (Oct. 15, 2009), but a Deep Space Network (DSN) station outage at the last minute prevented the commands from reaching the rover.

On Sol 2058 (Oct. 17, 2009), the commands were successfully sent to the rover that cleared the X-band and HGA errors and resumed normal HGA X-band operation. Spirit went on to conduct several days of Mössbauer (MB) spectrometer integration on the surface target "Thoosa" and to search for dust devils with the navigation camera (Navcam).

On Sol 2059 (Oct. 18, 2009), more panoramic camera (Pancam) images of "Scamander Plains" were collected along with miniature thermal emission spectrometer (Mini-TES) observations of the target "Pioneer." Early in the morning of Sol 2061 (Oct. 20, 2009), the rover woke up to characterize the Tstat box. On that sol, Spirit also collected another 11-frame microscopic imager (MI) mosaic of the underbelly of the rover and set up for more MB integration on Thoosa.

As of Sol 2062 (Oct. 21, 2009), Spirit's solar-array energy production is 410 watt-hours, with an atmospheric opacity (tau) of 0.570 and a dust factor of 0.594. Total odometry remains at 7,729.97 meters (4.80 miles).


sols 2050-2055, October 09-14, 2009: In X-Band Fault Mode

Spirit is still in X-band fault mode due to a high-gain antenna (HGA) dynamic brake anomaly that first occurred back on Sol 2027 (Sept. 15, 2009) and has re-occurred most recently on Sol 2052 (Oct. 11, 2009). With the HGA fault, all X-band uplinks use the low-gain antenna (LGA) and uplink bandwidth is limited.

Spirit was to be back under normal HGA operation on Sol 2054 (Oct. 13, 2009). However, a Deep Space Network (DSN) station outage at the last minute, with no alternative station available, prevented the HGA-recovery uplink from getting to Spirit. Spirit will be under runout sols, and the next planned uplink will be on Sol 2057 (Oct. 16, 2009). So the Sol 2057 plan is to clear the X-band and HGA faults and change the communication behavior manager (CBM) back to X-band nominal. The HGA dynamic brake status has been masked already in flight software.

Spirit is otherwise in good health (power positive, thermally stable and communicative over LGA and UHF) conducting limited remote sensing science in the runout sols. The Mössbauer (MB) spectrometer is positioned on a surface target and will resume an extended integration on Sol 2057 (Oct. 16, 2009).

As of Sol 2054 (Oct. 13, 2009), Spirit's solar array energy production was 427 watt-hours with an atmospheric opacity (tau) of 0.605. The dust factor is 0.6075, meaning that about 61 percent of the sunlight hitting the solar array is penetrating through the dust on the array.

Total odometry as of Sol 2055 (Oct. 14, 2009): 7,729.97 meters (4.80 miles).


sols 2042-2049, September 30 - October 08, 2009: Busy with Antenna Brake Testing and Underbelly Imaging

Spirit is still currently in X-band fault mode due to a high-gain antenna (HGA) dynamic brake anomaly that first occurred on Sol 2027 and recurred again on Sol 2037. With this HGA fault, all X-band uplinks use the low-gain antenna (LGA), and uplink bandwidth is very limited. Forward-link commanding through Mars Odyssey is being used for all large commanding sequences like data management bundles and science sequencing.

On Sol 2044, Spirit completed another Microscopic Imager (MI) mosaic of the underneath of Spirit for extraction analysis, along with another test of the HGA dynamic brake. Results of that brake test were largely nominal. The current plan is to bring Spirit out of the X-band fault mode on Sol 2050 and perform a long-duration HGA motion test before resuming normal HGA operation. Spirit's systems are otherwise in good health.

As of Sol 2049, the rover solar array energy production was 423 watt-hours with an atmospheric opacity (tau) of 0.657 and a dust factor of 0.603.

Total odometry as of Sol 2049: 7,729.93 meters.


sols 2035-2041, September 23-29, 2009: Intermittent Problem with Antenna Brake

Spirit had a reoccurrence of the dynamic brake fault with the high-gain antenna (HGA) on Sol 2037 (Sept. 25, 2009) during the attempt to restore normal usage of the HGA. The dynamic brake problem is more frequently intermittent, requiring an alternate approach to resolving the problem. Until the HGA can be restored, the low-gain antenna (LGA) and forward-link commanding through the Mars Odyssey relay will be used.

The low bandwidth over the LGA and the latency with forward-link commanding limits the pace of recovery. The project is implementing a more exhaustive set of diagnostics on the HGA dynamic brake. Those diagnostics should illuminate the nature of the dynamic brake problem and guide the recovery strategy. Despite the HGA problem, Spirit will collect an extended panorama of her underbelly using the microscopic imager (MI) on the end of the robotic arm (IDD) and then place the Mössbauer (MB) spectrometer on a surface target for a long integration. Spirit is otherwise in good health.

As of Sol 2041 (Sept. 29, 2009), Spirit's solar-array energy production is 437 watt-hours. Atmospheric opacity (tau) is 0.727. The dust factor is 0.614, meaning that meaning that about 61.4 percent of the sunlight hitting the solar array is penetrating through the dust on the array. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 2029-2034, September 17-22, 2009: Progress on Antenna Actuator

Spirit is recovering from the high-gain antenna (HGA) anomaly that occurred on Sol 2027 (Sept. 15, 2009). The HGA problem is suspected to be an apparent intermittent behavior in the dynamic brake relay for the HGA actuators, a problem that has been seen and mitigated before in other rover actuators. Diagnostics were run on the HGA and each actuator moved freely in both directions without problems with the dynamic brake behaving normally.

The challenge for the rover team has been trying to uplink HGA recovery sequences over the low-gain antenna (LGA). Data rates over the LGA are so low that there is often insufficient time in the uplink window to get up all the necessary commands. Because of that, the project is using forward link UHF relay commanding through Mars Odyssey. The forward link has the additional complication that there is additional latency in getting the commands to the rover, so the pace of recovery is impacted. Return to normal HGA usage for Spirit is anticipated by next week. Spirit is otherwise in good health.

As of Sol 2033 (Sept. 21, 2009), Spirit's solar-array energy production was 418 watt-hours with an atmospheric opacity (tau) of 0.972 and a dust factor of 0.626. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 2022-2028, September 10-16, 2009: Diagnostics on Antenna Actuator

Spirit is continuing science investigations with remote-sensing and robotic-arm instruments while positioned at her embedded location on the west side of Home Plate.

Spirit began the week with the alpha particle X-ray spectrometer (APXS) examining dust on the capture magnet located up on the rover deck. On Sol 2024 (Sept. 12, 2009), the robotic arm (instrument deployment device, or IDD) collected another microscopic imager (MI) mosaic of the rover underbelly, then took a stack of MI images of the surface target "Penina4" followed by the APXS placement on the same target. On the next sol the Mössbauer (MB) spectrometer was placed on Penina4.

On Sol 2027 (Sept. 15, 2009), a high-gain antenna (HGA) fault occurred. Telemetry indicates anomalous behavior with the dynamic brake on the HGA actuators. Diagnostics are underway and a likely workaround is in development. Spirit is otherwise in good health.

As of Sol 2028 (Sept. 16, 2009), Spirit's solar-array energy production is 403 watt-hours with an atmospheric opacity (tau) of 1.21 and a dust factor of 0.631. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 2015-2021, August 27 - September 09, 2009: Examining Target 'Olive Leaf'

Spirit is continuing remote sensing and in situ science while positioned at her embedded location on the west side of Home Plate.

On Sol 2015 (Sept. 3, 2009), a Mössbauer (MB) integration was completed on target "Olive Leaf." On the next sol, a rock abrasion tool (RAT) calibration and a RAT diagnostics were performed, then the APXS was placed on Olive Leaf for an overnight integration. On the sol after that, the robotic arm (instrument deployment device, or IDD) positioned the microscopic imager (MI) to take an image of the capture magnet on the rover deck. Then the alpha particle X-ray spectrometer (APXS) was placed on that magnet for a multi-sol integration.

The panoramic camera (Pancam) was busy taking 13-filter images of "Scamander Plains" and documentary images of the rover deck.

Ground testing continued at JPL with tests using the Mars-weight surface system testbed (SSTB Lite) rover with its center-of-gravity over a rock.

As of Sol 2021 (Sept. 3, 2009), Spirit's solar-array energy production is 418 watt-hours, with an increased atmospheric opacity (tau) of 1.65 and a dust factor of 0.669. Rover power plans have been conservative because of the elevated atmospheric opacity. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 2009-2014, August 27 - September 02, 2009: Sky Clearer at 'Troy,' Smoky at JPL

Spirit is positioned at her embedded location, called "Troy," on the west side of Home Plate. The regional dust storm that had dusted up the skies over Gusev has abated and the skies are clearing. Atmospheric opacity (tau) has decreased and rover solar-array performance has improved.

The week's activities for both rovers have been impacted by problems with other spacecraft that resulted in lost Deep Space Network (DSN) coverage for the rovers. Because there was no DSN uplink available for Spirit on Sol 2009 (Aug. 27, 2009), the rover executed an onboard run-out sequence. Later in the week, planning for Spirit was impacted again when wildfires near the Jet Propulsion Laboratory (JPL) forced closure of the laboratory for air-quality reasons on Aug. 31, 2009. So Spirit executed another run-out sol on Sol 2013 (Sept. 1, 2009).

On Sol 2014 (Sept. 2, 2009), Spirit resumed normal (master sequence) operation and continued with a Mössbauer (MB) integration on the target "Ulysses Spear." Before the wildfires, ground testing was completed with the two different weight engineering test rovers in two different soil stimulants at JPL. A Mars Program-level review was held on Sept. 2, 2009, of the Spirit recovery effort.

As of Sol 2014 (Sept. 2, 2009), Spirit's solar-array energy production has increased to 564 watt-hours. By Sol 2013 (Sept. 1, 2009), the atmospheric opacity (tau) had improved to 0.890 (Sol 2013) and the dust factor had recovered to 0.720, meaning that about 72 percent of the sunlight hitting the solar array was penetrating through the dust on the array. Spirit's total odometry remains at 7,729.93 meters (4.80 miles).


sols 2002-2008, August 20-26, 2009: Regional Dust Storm

Spirit continues to profile the geology at her embedded location, called "Troy," on the west side of Home Plate. However, the rover is currently affected by a large regional dust storm.

Although orbital observations indicate the storm is abating, the skies over Gusev crater are expected to remaining dusty for several sols. As a result, the rover team has been conservative with Spirit's planning, keeping energy consumption low and maintaining high states of charge in the batteries until the skies clear.

Spirit began the week continuing a long Mössbauer (MB) integration of the surface target "Polyphemus Eye." On Sol 2006 (Aug. 24, 2009), Sprit initiated a set of penetrometer experiments to directly measure physical properties of the embedding soil. The rock abrasion tool (RAT) was pressed into the soil at three different pre-load levels of force. The resulting indentation (soil penetration) after each pre-load was then documented with a set of images. Also on the same sol an atmospheric argon measurement was collected with the alpha particle X-ray spectrometer (APXS), and the MB was placed for another multi-sol integration.

On Earth, testing is being done with two different-weight rovers, the full-weight surface system testbed (SSTB) rover and the near Mars-weight SSTB Lite rover, in two different soil simulants. Testing with both rovers will help determine the effects of different gravity on Earth-based test results, all in preparation for the first extraction moves on Mars.

Atmospheric conditions have deteriorated owing to the large regional dust storm. As of Sol 2007 (Aug. 25, 2009), Spirit's solar-array energy production was precipitously down to 322 watt-hours, with a large increase in the atmospheric opacity (tau) to 2.61. The dust factor declined to 0.658, meaning that about 65.8 percent of the sunlight hitting the solar array penetrates through the dust on the array. Spirit's total odometry remains at 7,729.93 meters (4.80 miles).


sols 1995-2001, August 13-19, 2009: More than 2,000 sols

Spirit has passed 2,000 sols on the surface of Mars, yet another milestone. Starting its third sol millennia, Spirit continues to profile the geology at the location where the rover is embedded, a site called "Troy" on the west side of "Home Plate."

On Sol 1995 (Aug. 13, 2009), Spirit continued the campaign of grinding deeper into surface targets, then collecting in situ (contact) measurements at each grind depth. The rock abrasion tool (RAT) executed a grind on the target "Polyphemus_Eye_2." Then the panoramic camera (Pancam) and the microscopic imager (MI) took images of where the grind had been performed, and the robotic arm placed the alpha particle X-ray spectrometer (APXS) on the freshly-ground target. On the next sol, the rover changed tools to the Mössbauer (MB) spectrometer and placed it on the target for an overnight integration. The rover continued on the next sol with an MI mosaic of a different target, "Olive_Leaf," followed by an APXS placement on that target. On the following sol, the MB was placed on target Polyphemus for a multi-sol integration.

On Earth, the surface system testbed (SSTB) rover extraction testing continues in preparation for the first extraction moves on Mars.

Atmospheric conditions over Spirit have deteriorated owing to a regional dust storm. As of Sol 2001 (Aug. 19, 2009), the rover solar-array energy production was down to 744 watt-hours with atmospheric opacity (tau) increasing to 0.718 and the dust factor remaining around 0.8315. Spirit's total odometry remained at 7,729.93 meters (4.80 miles).


sols 1989-1994, August 07-12, 2009: Deeper Look into Soil Targets

Spirit continues to profile the geology at the rover's embedded location, called "Troy," on the west side of the low plateau called Home Plate.

On Sol 1990 (Aug. 8, 2009), Spirit continued the campaign of grinding deeper into surface targets, then collecting contact measurements at each grind depth. The rock abrasion tool (RAT) performed a grind on the target Cyclops_Eye_6, followed by imaging of the resulting surface by the panoramic camera (Pancam) and the microscopic imager (MI). The MI also took a new look at the underbelly of the rover to further assess possible obstruction by a rock underneath.

Before an attempt to have the robotic arm (instrument deployment device, or IDD) place the Mössbauer (MB) spectrometer on the surface, a command sequence fault occurred with the arm. This fault was explained as a benign error that occurs from time to time due to very small positioning errors in the IDD. With this error investigated, understood and cleared, the IDD went on to have the RAT perform a grind scan on Sol 1993 (Aug. 11, 2009) in preparation for another profile grind.

On Earth, the surface system testbed (SSTB) rover extraction testing continues in preparation for Spirit's first extraction moves on Mars.

As of Sol 1994 (Aug. 12, 2009), Spirit's solar-array energy production is 895 watt-hours with atmospheric opacity (tau) of 0.352 and a dust factor of 0.844 on the solar array. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1981-1988, July 30 - August 06, 2009: Illumination Experiment and Other Studies

Spirit's examination of the soil around the rover using tools on the robotic arm (instrument deployment device, or IDD) continued this week with Mössbauer (MB) spectrometer on target "Cyclops Eye" and microscopic imaging of target "Penina." On Sol 1986 (Aug. 4, 2009), the rock abrasion tool (RAT) was prepared for grinding into the target Cyclops Eye on a later sol.

With the surplus of power, Spirit continues to perform science observations at a variety of times. This includes an illumination experiment, which consists of a set of navigation camera observations acquired at different times of day to help examine texture in the terrain. The resulting information could aid future driving.

On Earth, the surface system testbed (SSTB) rover extraction testing continues with end-to-end testing in differentiated soil in preparation to the first extraction moves on Mars.

As of Sol 1988 (Aug. 6, 2009), Spirit's solar array energy production is 907 watt-hours with atmospheric opacity (tau) of 0.330 and dust factor of 0.821 on the solar array. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1975-1980, July 24-29, 2009: Robotic Arm Diagnostics

Spirit is continuing its ambitious remote sensing and in-situ (contact) science campaign using all her payload elements while embedded at the location called Troy on the west side of Home Plate.

During in situ (contact) work with the robotic arm on Sol 1975 (July 24, 2009), the Instrument Deployment Device (IDD) Joint 2 (shoulder elevation) stalled. The stall occurred between two Microscopic Imager (MI) mosaics. A series of diagnostics were sequenced on Sol 1979 (July 28, 2009).

The diagnostics included an elbow and turret motion (Joints 3, 4 and 5) to reduce torque on Joint 2, a rotor resistance test of the Joint 2 motor, and then a series of small Joint 2 diagnostic motions, a MI mosaic and a placement of the alpha particle X-ray spectrometer (APXS) on a surface target. The IDD Joint 2 motor resistances are normal and the IDD Joint 2 moved successfully to all commanded diagnostic motions. All MI images were taken and the APXS is positioned on the surface target. There are no mobility/IDD errors or preclusions. The IDD Joint 2 appears to be okay.

On Earth, the surface system testbed (SSTB) rover extraction testing continues with end-to-end testing in differentiated soil in preparation for the first extraction moves on Mars.

As of Sol 1980 (July 29, 2009), the rover solar array energy production was 914 watt-hours, with atmospheric opacity (tau) of 0.380 and a dust factor of 0.831.

Total odometry as of Sol 1980 (July 29, 2009): 7,729.93 meters (4.80 miles)


sols 1968-1974, July 16-23, 2009: Poking 'Cyclops Eye'

Spirit, positioned on the west side of Home Plate, continues to be engaged in ambitious remote sensing and in-situ (contact) science using all her payload elements. The embedding of the rover back on Sol 1899 (May 6, 2009) has exposed a subsurface emplacement of likely remobilized minerals with a strong water association.

On Sol 1968 (July 16, 2009), the microscopic imager (MI) collected images for a mosaic of the surface target "Olive." Then, the Mössbauer (MB) spectrometer was placed on target "Cyclops_Eye_4" for a multi-sol integration over the weekend. On Sol 1972 (July 20, 2009), the rock abrasion tool (RAT) performed a seek-scan procedure in preparation for a RAT grind of a surface target. On the next sol, the RAT ground the target "Cyclops_Eye_5" and then the APXS was placed for an integration.

The rover's panoramic camera (Pancam) and miniature thermal emission spectrometer (Mini-TES) continue to collect observations of selected remote targets, including detailed images of the vertical section of the west side of Home Plate.

The surface system testbed (SSTB) rover continues to be used in extraction testing in a simulated-Mars sandbox at JPL. Testing in undifferentiated soil is complete. The test sandbox will be reconfigured to allow testing in differentiated soil. Differentiated soil is what is seen by the rover on Mars.

As of Sol 1974 (July 23, 2009), Spirit's solar array energy production is 935 watt-hours with atmospheric opacity (tau) of 0.376. On Sol 1973 (July 22, 2009), the dust factor was 0.819, indicating that 84.4 percent of sunlight hitting the array was penetrating the layer of dust on it. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1961-1967, July 9-15, 2009: More Soil Studies and Extraction Tests

Spirit, positioned on the west side of Home Plate, has been continuing her ambitious science campaign of remote sensing and in-situ (contact) science using all her payload elements.

On Sol 1963 (July 11, 2009), the robotic arm (instrument deployment device, or IDD) retracted the rock abrasion tool (RAT) from the surface where it had been positioned by an earlier placement. The rover then performed a RAT calibration, collected a stack of images from the microscopic imager (MI), and replaced the RAT on the target to do a seek-scan procedure for locating the surface.

On Sol 1965 (July 13, 2009), a RAT brushing was performed on the target. At the completion of the RAT brushing, the IDD was swung out of the way. On the next sol, an MI mosaic was collected of the brushed target and the alpha particle X-ray spectrometer (APXS) was placed for an overnight integration. On Sol 1967 (July 15, 2009), the IDD positioned the instruments over another target and collected an MI mosaic before placing the APXS.

The rover is continuing nighttime activities to increase the depth of discharge in the batteries for battery health and maintenance.

The surface system testbed (SSTB) rover extraction testing in a simulated-Mars sandbox at JPL continues. Several extraction tests have been performed with more to be conducted in coming days.

As of Sol 1967 (July 9, 2009), Spirit's solar array energy production is 944 watt-hours. Atmospheric opacity (tau) is 0.398. The dust factor on the solar array is 0.844, indicating that 84.4 percent of sunlight hitting the array penetrates the much-reduced layer of dust on it. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1953-1960, July 1-8, 2009: Active Days and Nights

Spirit remains positioned just west of Home Plate, in the location called "Troy," where the rover has been continuing an ambitious science campaign.

The campaign includes extensive observations with the panoramic camera (Pancam) and miniature thermal emission spectrometer (Mini-TES) plus contact science using all the tools on the robotic arm (instrument deployment device, or IDD). On Sol 1954 (July 2, 2009), the rock abrasion tool (RAT) repeated a seek-scan procedure on a surface soil target in preparation for brushing that target, but the seek-scan was unable to make sufficient contact with the target for brushing.

With abundant daily energy after repeated array-cleaning events, the rover is conducting nighttime activities to increase the depth of discharge in the batteries for battery health and maintenance.

Activities continue on Earth for extraction testing of the surface system testbed (SSTB) rover in a simulated Mars environment. On July 6, 2009, testing began with the SSTB on the series of proposed extraction maneuvers in the new test fixture ("dust bin") at JPL.

As of Sol 1960 (July 8, 2009), Spirit's solar array energy production is 938 watt-hours. Atmospheric opacity (tau) is 0.349. The dust factor on the solar array is 0.82, indicating that 82 percent of sunlight hitting the array penetrates the much-reduced layer of dust on it. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1948-1952, June 26-30, 2009: Soil Investigation Continues

Spirit remains positioned on the west side of Home Plate. The rover has been continuing an ambitious science campaign of extensive observations with the panoramic camera (Pancam) and miniature thermal emission spectrometer (Mini-TES) plus contact science using using all the tools on the robotic arm (instrument deployment device, or IDD).

On Sol 1948 (June 26, 2009), the IDD placed the Mössbauer (MB) spectrometer on the target called "Cyclops_Eye_3" for a multi-sol integration. On Sol 1952 (June 30, 2009), the rock abrasion tool (RAT) was calibrated. Then, a RAT grind-scan was performed on a surface target in preparation for brushing that target.

With abundant daily energy, the rover continues to conduct nighttime activities to increase the depth of discharge in the batteries for battery health and maintenance.

Activities continue on the ground for extraction testing of the surface system testbed (SSTB) rover in a simulated Mars environment. Several tons of soil simulant were mixed and prepared in the new test fixture (sandbox) at JPL. On June 30, 2009, the SSTB was driven into this new test sandbox in preparation for the extraction tests.

As of Sol 1951 (June 29, 2009), Spirit's solar array energy production is at 927 watt-hours, with atmospheric opacity (tau) of 0.356 and dust factor of 0.798. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1941-1947, June 18-24, 2009: Studying Troy

Spirit is continuing her ambitious remote sensing and in-situ (contact) science observations at the location called "Troy" on the west side of Home Plate.

Using the rover robotic arm (instrument deployment device, IDD), the rover has been exploring a set of surface targets that hold clues to the past geologic history at this location.

On Sol 1941 (June 18, 2009), a Microscopic Imager (MI) stack of images was collected on target Penina3, then the Alpha Particle X-ray Spectrometer (APXS) was placed for an overnight integration. On the next sol, the Mössbauer Spectrometer (MB) was placed on a different target for a multi-sol integration. The next few sols included some late-day activities where the rover imaged the Earth and Venus in the night sky.

On Sols 1945 and 1946 (June 22 and 23, 2009), Spirit investigated another set of surface targets, again with MI stacks and APXS overnight integrations. On Sol 1946 (June 23, 2009), another solar array dust cleaning event occurred, increasing the available energy each sol even more.

At JPL, a special test form has been installed for ground testing with the surface system testbed (SSTB) rover to guide the eventual extraction activities on Mars for Spirit. The materials for the soil simulant to be used in the test form have been delivered and are in the process of being formulated and mixed. As of Sol 1947 (June 24, 2009), solar array energy production increased to 945 watt-hours with atmospheric opacity (tau) of 0.480 and an improved dust factor of 0.834. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1934-1940, June 11-18, 2009: Soil Investigation

Spirit remains stationary on the west side of Home Plate in the location called "Troy". The rover continues to be busy with an ambitious observation campaign employing both remote sensing and in-situ (contact) science with the robotic arm (instrument deployment device, IDD).

The soil disturbed by the rover's embedding has been the subject of extensive science investigation. Five out of the past seven sols have involved using the instruments on the end of the robotic arm to collect images and composition spectra of five distinct targets. Images from the panoramic camera (Pancam) and spectra from the miniature thermal emission spectrometer (Mini-TES) have also been collected. Extensive nighttime observations have been planned to make use of the abundant energy the rover has right now.

At JPL, preparations are continuing for ground testing with the surface system testbed (SSTB) rover. A special test form has been constructed to hold the new soil simulant that will recreate Spirit's martian terrain. The new simulant has been validated with single-wheel "shoebox" testing by the SSTB rover. Large quantities of simulant ingredients have been ordered and are expected within days.

As of Sol 1939 (June 17, 2009), Spirit's solar array energy production is at 853 watt-hours, with atmospheric opacity (tau) of 0.486 and a dust factor of 0.760. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1927-1933, June 04-10, 2009: Observation Campaign at 'Troy'

Spirit remains stationary on the west side of Home Plate. Work continues on developing the ground testing to assist the rover in extracting itself from the embedding in this location, called "Troy".

The rover has been busy with an ambitious observation campaign employing both remote sensing and in-situ (contact) science with the robotic arm (instrument deployment device, IDD). The soil, disturbed by the rover embedding, reveals unconsolidated, light-toned material. Analysis indicates this material consists of differing amounts of ferric sulfate, calcium sulfate, silica and other constituents.

On Sol 1927 (June 4, 2009), the IDD used the microscopic imager (MI) to collect a stack of stereo images, then placed the alpha particle X-ray spectrometer (APXS) for an overnight integration. On the next sol, the APXS was moved to a different surface target for a second integration. On Sol 1929 (June 6, 2009), another set of MI images was collected and the Mössbauer (MB) spectrometer was placed for a multi-sol integration.

On Sol 1933 (June 10, 2009), a full-rotation test was performed on the left-middle wheel to explore a stall event from Sol 1899 (May 6, 2009). The test successfully rotated the wheel one full rotation backwards and more than one full rotation forward past the point of the original stall. The wheel moved freely with no re-occurrence of a stall.

Preparation for ground testing of embedding extraction techniques continues. A soil simulant has been established by way of a series of "shoebox" (single wheel) tests of candidate materials with the surface system testbed (SSTB) rover in the sandbox at JPL. A test form to contain rover-scale quantities of soil simulant is under construction.

As of Sol 1932 (June 9, 2009), Spirit's solar array energy production is at 828 watt-hours, with atmospheric opacity (tau) of 0.502 and a dust factor of 0.749. Total odometry remains at 7,729.93 meters (4.80 miles).


sols 1920-1926, May 28 - June 03, 2009: Underbelly Photography

Although Spirit has yet to begin to extricate herself from the loose, soft terrain on the west side of Home Plate, the rover has been active using her instruments to assess her embedded state.

This week the robotic arm (Instrument Deployment Device, IDD) with the Microscopic Imager (MI) were used to take a mosaic of images of the rover's underbelly. The MI, a short focus camera, was never designed to take these types of long-focus images. This technique was first tested by Opportunity and the test demonstrated that although the images will not be sharply focused, sufficient detail can be seen.

Spirit's first MI mosaic of the underbelly was collected on Sol 1922 (May 30, 2009). The IDD then positioned the MI to collect a stack of images of a science soil target and placed the Mössbauer (MB) spectrometer on the science target for a multi-sol integration. Spirit collected a second underbelly image mosaic on Sol 1925 (June 2, 2009). This time the IDD extended further under the rover to capture more detail. The IDD then collected another MI stack of images of a science target followed by the placement of the Alpha-Particle X-ray Spectrometer (APXS) on the same target. Frames of a 360-degree color panorama, called the Calypso panorama, were collected. Targeted observations were made with the miniature thermal emission spectrometer.

The project was successful in restoring files to a computer server so that the surface system testbed (SSTB) rover at JPL could be operated. Soil simulant tests with the SSTB were performed on "Bag House" dust simulant. Unfortunately, the test results show that the Bag House dust is not suitable as a simulant for Spirit's situation. A new simulant is being formulated and will be tested shortly.

As of Sol 1926, solar array energy production was generous at 884 watt-hours with atmospheric opacity (tau) of 0.458 and a dust factor of 0.772. Spirit's total odometry remains at 7,729.93 meters (4.80 miles).


sols 1913-1919, May 21-27, 2009: Recovery Efforts Continue

p>Spirit remains stationary, pending development of a recovery strategy to free her from the loose, soft terrain on the west side of Home Plate.

The rover continues to conduct extensive remote sensing observations of its local terrain. A 360-degree color panorama, called the Calypso panorama, is being collected, and includes the rover's deck. Additional mini-thermal emission spectrometer (TES) observations have been sequenced. Thanks to the extra energy made possible by recent solar array dust cleaning events, Spirit has been collecting measurements of atmospheric argon almost every day using its alpha-particle X-ray spectrometer (APXS).

The project continues to investigate the left middle wheel stall that occurred back on Sol 1899 (May 6, 2009). A small (4-degree) backward wheel motion test was sequenced on Sol 1913 (May 21, 2009). The wheel and motor performed satisfactorily. A second, larger test (16 degrees) was performed on Sol 1916 (May 24, 2009), and again, the wheel performed satisfactorily, showing no signs of a jam in the backward direction.

Pending the recertification of the robotic arm (the instrument deployment device, or IDD), a microscopic imager (MI) mosaic of Spirit's underbelly is planned for this coming weekend to assess the rover's embedded condition.

On the ground, testing with the surface system testbed (SSTB) rover at JPL is held up due to a computer server disk crash. That server is being restored from a huge backup tape, which is taking considerable time. In parallel, the SSTB-Lite rover (an alternate, lower-fidelity testbed rover) is being set up to conduct early tests of candidate soil simulants.

Spirit is very active, with abundant energy. Once again, Spirit has received a beneficial solar array dust cleaning. Dust factor (a measure of array cleanliness) improved about 10 percent on Sol 1918 (May 26, 2009). As of Sol 1919 (May 27, 2009), solar array energy production was 843 watt-hours, enough to run a 100-watt bulb for more than eight hours, with atmospheric opacity (tau) around 0.606. The dust factor increased to 0.774, meaning that about 77.4 percent of the sunlight hitting the solar array penetrates through the dust on the array.

Spirit's total odometry as of Sol 1919 (May 27, 2009) is 7,729.93 meters (4.8 miles).


sols 1907-1912, May 15-20, 2009: Spirit Works on Exit Strategy

Rover team members continue their recovery strategy to extricate Spirit from the loose, soft terrain on the west side of "Home Plate." The rover continues to conduct extensive remote sensing observations of the local terrain.

With the extra energy Spirit has gained from recent solar array dust cleaning events, morning UHF relay passes have been added. A low-voltage continuity test of the motor on the left middle wheel was performed on Sol 1908 (May 16, 2009). The results showed normal resistance for a healthy motor. Even though very small voltages were used in that test, a tiny amount of motion (less than a degree) was observed. This is not unexpected, as the motion was opposite of the apparent jam from Sol 1899 (May 6, 2009) and is likely due to the unwinding (relaxation) of the strain in the 1500:1 gearbox. The small motion means it is now less likely there is a jam in the gearbox. A small 4-degree backward wheel motion test is planned for Sol 1913 (May 21, 2009) to investigate the wheel further.

On the ground, work continues on the preparation of the sandbox at JPL to recreate the terrain and conditions of the rover on Mars. A "shoebox" test of a soil simulant, called Bag House dust (a ground basaltic cinder), will be performed under one wheel of the surface system testbed (SSTB) rover to see if the simulant exhibits the characteristics of the soil on Mars. However, testing with the SSTB rover at JPL is held up due to a computer server disk crash. That server loss is being remedied, but will take some time.

As of Sol 1912 (May 20, 2009), solar-array energy production was 716 watt-hours, with atmospheric opacity (tau) around 0.628 and the dust factor improved to 0.680. Spirit has been responsive and communicative, with no reoccurrence of the anomalies from 30 sols ago.

As of Sol 1912 (May 20, 2009), Spirit's total odometry remains 7,729.93 meters (4.8 miles).


sols 1900-1906, May 07-14, 2009: Embedded and Cleaner

Spirit is embedded in loose, soft terrain on the west side of Home Plate. There is a real risk the rover may be high-centered (underside touching) on a small mound of rocks right under the belly of the rover. Additionally, a left wheel motor stall occurred during the last rover motion on Sol 1899 (May 6, 2009). No motion has been commanded since.

The project is engaged in a recovery activity. This involves extensive remote sensing observations by the rover of the local soil characteristics, and ground testing using the surface system testbed rover in the sandbox at JPL.

There has been no recurrence of the anomalous behavior that happened between Sol 1872 (April 9, 2009) and Sol 1881 (April 18, 2009). There is still no explanation for the previous anomalies, and the investigation is continuing.

The week provided more good news about solar array energy. Spirit experienced yet another substantial solar array dust cleaning event. On Sol 1900 (May 7, 2009), energy production improved by about 30 percent. With the significant improvement in energy, the rover can now support morning UHF relay passes, which will help with the backlog of collected data onboard. The Mars Odyssey project has made special efforts to support this additional relay.

As of Sol 1905 (May 13, 2009), solar array energy production is estimated around 652 watt-hours, with atmospheric opacity (tau) at 0.774. The dust factor has improved substantially to 0.678, meaning that 67.8 percent of sunlight hitting the solar array penetrates the layer of dust on the array. As of Sol 1906 (May 14, 2009), Spirit's total odometry remains 7,729.93 meters (4.80 miles).


sol 1893-1899, April 30 - May 06, 2009: Another Power Boost, But Difficult Driving

Spirit has now completed 19 sols of operation without any recurrence of the anomalous behavior that happened between Sol 1872 (April 9, 2009) and Sol 1881 (April 18, 2009). In addition to changes made to the rover's wake-sleep cycle and internal data logging, a new ability to detect "amnesia" events has been implemented. There is still no explanation for the previous anomalies, and the investigation is continuing.

Spirit is currently challenged by some very difficult terrain on the west side of Home Plate. The rover encountered very loose, soft material while driving south on its current path. So Spirit is now in the process of backing out. However, with only five driving wheels, its progress has been very difficult. Only centimeters have been achieved over the last four drive sols. It is expected that extracting Spirit from this location will require many more drive sols.

The good news is that Spirit experienced another solar array dust cleaning event. On Sol 1899 (May 6, 2009), energy production improved by more than 25 percent.

As of Sol 1899 (May 6, 2009), Spirit's solar array energy production is about 500 watt-hours, equivalent to what is needed to light a 100-watt bulb for five hours. Atmospheric opacity (tau) is at 0.821. The dust factor has improved substantially to 0.515, meaning that about 51.5 percent of sunlight hitting the solar array penetrates the layer of dust on the array. Spirit has more solar array energy than Opportunity for the first time in a very long time. Spirit's total odometry is 7,729.93 meters (4.80 miles).


sol 1886-1892, April 23-29, 2009: Well Behaved, Less Dusty, in Difficult Terrain

Spirit has completed 11 consecutive sols of operation without any faults or resets. Anomalous behavior from the period after Sol 1872 (April 9, 2009) has not recurred. There is still no explanation for those anomalies, and the investigation is continuing.

Changes were made to rover wake-sleep cycle to be more resilient against any future "amnesia" occurrences. Also, changes were made to record internal data for a longer period of time if the rover again misses any wakeups. Four drive sols were successfully executed this week. However, the terrain, once again, is very difficult, and the rover achieved very limited progress. The rover drove on sols 1886, 1889, 1891 and 1892 (April 23, 26, 28 and 29, 2009), covering a total of about 3 meters (10 feet).

Spirit experienced another small solar array dust cleaning event. On Sol 1891, energy production improved by more than 10 percent, supplementing a similar improvement the previous week.

As of Sol 1892 (April 29, 2009), Spirit's solar array energy production is about 372 watt-hours, compared with 223 watt-hours at the end of March (Sol 1864). Atmospheric opacity (tau) is around 0.855. The dust factor has improved to around 0.418, meaning that about 41.8 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover's behavior has been good and responsive, and solar energy production is well improved. Spirit's total odometry is 7,729.73 meters (4.80 miles).


sol 1879-1885, April 16-22, 2009: Another Reset and a Cleaning Event

Spirit experienced another reset event over the weekend, but otherwise has been well-behaved.

The investigation into Spirit's recent anomalous behavior continues, but there is still no explanation. A team of experts involved in the original design and construction of the rover has been consulted. Although the anomalous behavior is frustrating, the rover continues to be healthy in terms of power, temperature and communication.

The plan going forward is to implement some enhanced data-collecting techniques in order to gather more information from any future anomalous events, and to resume near-normal operations. A short drive for Spirit has been sequenced on Sol 1886 (April 23, 2009).

Spirit also had a small dust cleaning event on her solar arrays on Sol 1881 (April 18, 2009). Solar array energy improved by more than 10 percent

As of Sol 1885 (April 22, 2009), Spirit's solar array energy production is 306 watt-hours, about as much as is used in lighting a 100-watt bulb for three hours. Atmospheric opacity (tau) is estimated around 0.964. The dust factor has improved to about 0.377, meaning that about 37.7 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. Spirit's total odometry remains at 7,726.78 meters (4.80 miles).


sol 1872-1878, April 09-15, 2009:  Memory Gaps and Unexplained Resets

Spirit experienced a series of anomalous events beginning on Sol 1872 (April 9, 2009).

Spirit failed to wake up for three planned events. The rover eventually woke up from an expiring alarm clock timer 27 hours later. Then, an unexpected reset of the rover occurred on Sol 1874 (April 11, 2009). A second reset occurred on Sol 1875 (April 12, 2009). It was also discovered that the rover did not record any data in flash memory on sols 1874 and 1876 (April 11 and April 13, 2009).

Sols 1877 and 1878 (April 14 and April 15, 2009) have been normal without any errors or anomalies. At this time, there is no explanation for these anomalies. The rover is power positive with the batteries fully charging each day. All temperatures are well within allowable limits. The project is systematically resetting sub-systems to bring the rover back to normal operations while continuing to investigate this anomalous behavior. Normal, but cautious, operations are expected by the middle of next week.

As of Sol 1878 (April 15, 2009), Spirit's solar array energy production is 241 watt-hours, with atmospheric opacity (tau) around 0.964. The dust factor is around 0.316, meaning that about 31.6 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. Spirit's total odometry is 7,726.78 meters (4.80 miles).


sol 1865-1871, April 01-08, 2009:  Four Drives Add to Progress

Spirit has been busy making good progress around the western edge of "Home Plate." The rover drove four out of the past seven sols, making more than 40 meters (131 feet) of total distance.

First, Spirit completed a science campaign on light-toned material unearthed the preceding week, then the rover resumed driving on Sol 1866 (April 3, 2009; no sol number for Spirit corresponded to April 2, 2009, using the criterion of the date in Los Angeles at local solar noon on Mars). The Sol 1866 drive achieved only about 3 meters (10 feet) of progress due to excessive slip. On the next drive sol, Sol 1868 (April 5, 2009), Spirit avoided the troubled terrain and completed about 17.5 meters (57 feet). A pair of drives on Sols 1870 and 1871 (April 7 and 8, 2009) added another 20 meters (66 feet) of progress.

As of Sol 1871 (April 8, 2009), Spirit's solar array energy production is 240 watt-hours, equivalent to what it takes to light a 100-watt bulb for 2.4 hours. Atmospheric opacity (tau) has improved slightly to 0.99. The dust factor is 0.304, meaning that 30.4 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health as it makes progress around Home Plate. Spirit's total odometry is 7,726.78 meters (4.80 miles).


sol 1859-1864, March 26-31, 2009:  More Bright Soil Exposed by Driving

Spirit is running under new flight software, version R9.3, and all is working well. The rover continued driving around the west of "Home Plate."

A drive on Sol 1861 (March 28, 2009) achieved almost 23 meters (75 feet) and something extra. Light-toned soil was unearthed by the right-front wheel as the rover drove along this western portion of Home Plate. The science team, suspecting that this may be more silica, developed a contact science campaign for this revealed material. On Sol 1863 (March 30, 2009), the robotic arm (IDD) was deployed and extended to the light-toned soil. A microscopic imager (MI) stack of images was collected and then the alpha particle X-ray spectrometer (APXS) was placed right on the target soil. Integration with the APXS continued through Sol 1864 (March 31, 2009). Observations of this light-toned material were also made with the miniature thermal emission spectrometer (Mini-TES).

As of Sol 1864 (March 31, 2009), Spirit's solar array energy production is 223 watt-hours. Atmospheric opacity (tau) remains elevated at 1.19. The dust factor on the solar array has worsened slightly to 0.297, meaning that 29.7 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health despite dusty skies. Spirit's total odometry is 7,686.61 meters (4.78 miles).


sol 1852-1858, March 19-25, 2009:  Distance Record for Five-Wheel Driving

Spirit is making good progress around Home Plate to the west. After getting clear of troublesome rocks, Spirit drove 13.8 meters (45.3 feet) on Sol 1854 (March 21, 2009). The next drive, on Sol 1856 (March 23, 2009), achieved a new distance record for five-wheel driving. Spirit drove 25.82 meters (84.7 feet), beating the old record by about a meter. Spirit completed another drive of 12.9 meters (42.3 feet) on Sol 1858 (March 25, 2009).

The sol ahead will see the building of the new R9.3 flight software on board the rover. The rover will boot the new software on the subsequent sol.

As of Sol 1858 (March 25, 2009), Spirit's solar array energy production is 233 watt-hours. Atmospheric opacity (tau) remains elevated at 1.15. The dust factor on the solar array, 0.309, means that 30.9 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health in spite of dusty skies. Spirit's total odometry is 7,665.02 meters (4.76 miles).


sol 1845-1851, March 12-18, 2009:  Getting Away from a Trouble Spot

Although Spirit will now attempt the western route around the low plateau "Home Plate," it must first safely move away from difficult terrain around the northeast corner of Home Plate. One tactical concern was a potato-size rock near the inside of the right rear wheel that posed a risk of getting stuck inside the wheel. Short maneuvers on Sol 1845 (March 12, 2009) and Sol 1847 (March 14, 2009) carefully moved the rover away from this hazard. On Sol 1850 (March 17, 2009), Spirit moved about 5 meters (16 feet), getting completely away from this trouble spot.

Spirit also conducted some panoramic camera (Pancam) imaging and miniature thermal emission spectrometer (Mini-TES) spectral measurements of various science targets in the vicinity and performed an atmospheric argon measurement with the alpha particle X-ray spectrometer (APXS).

Atmospheric conditions have worsened lately over the Gusev site, although no storm conditions have been reported.

As of Sol 1851 (March 18, 2009), Spirit's solar array energy production has decreased to 230 watt-hours, down 18 percent from a week earlier. Atmospheric opacity (tau) has increased sharply, to 1.19. The dust factor on the solar array is 0.313, meaning that 31.7 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health in spite of dustier skies.

As of Sol 1850 (March 17, 2009), Spirit's total odometry is 7,612.49 meters (4.73 miles).


sol 1838-1844, March 05-11, 2009:  Change to Western Route

Spirit continued to struggle in local terrain on the northeast corner of "Home Plate." Several drive attempts failed to make significant progress to the east up the modest slopes consisting of loose material.

On Sol 1839 (March 6, 2009) a wheel diagnostic test was performed to make sure a wheel stall seen on an earlier sol was not an actuator problem. The actuator is fine.

Drives on sols 1839, 1841 and 1843 (March 6, 8 and 10, 2009) all reinforced the futility of attempting further drives in this direction. Therefore, the project decided to head Spirit in the other direction, west around Home Plate. Spirit will begin to head that way in the sols ahead.

As of Sol 1844 (March 11, 2009), Spirit's solar array energy production is 281 watt-hours. Atmospheric opacity (tau) is 0.755. The dust factor on the solar array is 0.317, meaning that 31.7 percent of sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health as it begins to head west around Home Plate.

As of Sol 1843 (March 10, 2009), Spirit's total odometry is 7,607.68 meters (4.73 miles).


sol 1831-1837, February 26 - March 04, 2009:  Slight Progress on New Route

After initially making good progress on a new route around "Home Plate" to the east, Spirit has been struggling in local terrain on the northeast corner of Home Plate. The route is difficult because the direction is up-slope with a lot of loose, fine material denying the five-driving-wheel rover good traction.

After getting about 15 meters (49 feet) away from Home Plate last week in just two drives, Spirit made only 1.4 meters of progress on Sol 1831 (Feb. 26, 2009). The next two drive sols accomplished only about 2 meters each. On Sol 1837 (March 4, 2009), Spirit had difficulty turning to face a new direction, again because of the soft terrain.

The plan is to back downslope a little, turn and attack the uphill grade a little more cross-slope.

As of Sol 1837 (March 4, 2009), Spirit's solar array energy production is 282 watt-hours, atmospheric opacity (tau) is 0.742, and the dust factor on the solar array is 0.320. The rover is in good health as it attempts to make its way around the northeast corner of Home Plate. Spirit's total odometry is 7,602.42 meters (4.72 miles).


sol 1824-1830, February 18-25, 2009:  Route Change

Spirit has been attempting to approach an on-ramp on the north side of "Home Plate" for the ascent up onto this low plateau. The terrain finally proved to be too difficult for the rover driving with only five wheels.

Spirit made a little over a meter (3 feet) of progress on Sol 1825 (Feb. 19, 2009) trying to move out of the soft terrain at the base of Home Plate and set up for a drive up onto Home Plate. On Sol 1826 (Feb. 20, 2009), a turn-in-place was sequenced to move the rover out of the wheel trenches created by recent driving, but the maneuver was unsuccessful. The project decided at that point to abandon that route onto Home Plate and to have Spirit head around Home Plate to the east.

On Sol 1829 (Feb. 24, 2009), Spirit made about 6 meters (20 feet) of progress away from Home Plate. On Sol 1830 (Feb. 25, 2009), another 9 meters (30 feet) of progress was made along the new route.

As of Sol 1829 (Feb. 24, 2009), Spirit's solar-array energy production was 273 watt-hours. Atmospheric opacity (tau) increased slightly, to 0.710. The dust factor on the solar array is 0.304, meaning that 30.4 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health as it heads on the new path.

Spirit's total odometry as of Sol 1830 (Feb. 25, 2009) is 7,596.20 meters (4.72 miles).


sol 1817-1823, February 11-17, 2009:  Another Cleaning

Spirit has been continuing attempts to reach an on-ramp for ascending onto "Home Plate." The terrain continues to be difficult for driving with five wheels. Because of limited progress on previous sols, on Sol 1818 (February 12, 2009), Spirit attempted a series of sharp backward arcs. Spirit executed 60-centimeter (2-foot) arcs 29 times, but, due to wheel slippage, the rover made only 17 centimeters (7 inches) of progress.

On Sol 1820 (February 14, 2009), the plan was to drive forward, away from Home Plate, and turn. The rover was successful in turning about 45 degrees, sufficient to get the wheels out of the soft terrain where they had been digging in. Spirit will next attempt the approach to Home Plate while avoiding some of the soft terrain that complicated previous approaches.

The team continues to track the performance of the rover's accelerometers.

Another small dust-cleaning event on Sol 1820 (February 14, 2009) -- the second one this month -- improved solar-array performance by an additional 10 percent.

As of Sol 1823 (February 17, 2009) Spirit's solar-array energy production improved to 275 watt-hours. Atmospheric opacity (tau) increased slightly to 0.530. The dust factor is 0.306, meaning that 30.2 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health.

Spirit's total odometry as of Sol 1822 (February 16, 2009) is 7,572.23 meters (4.71 miles)


sol 1810-1816, February 04-10, 2009:  Cleaning Event Aids Daily Energy

Spirit has been approaching a potential on-ramp for the ascent onto "Home Plate." The terrain has been difficult for the five-driving-wheel rover. At the start of the week, Spirit was able to maneuver around a rock that had hung up the right front wheel. On Sol 1811 (February 5, 2009), Sprit continued a counterclockwise, 3-meter arc into a channel that runs along Home Plate. On Sol 1813 (February 7, 2009), a cross-slope attempt was made to climb the roughly 16-degree ramp onto Home Plate. Little progress was made fighting the uphill slope. The next drive, on Sol 1816 (February 10, 2009), achieved little progress because the rover's motions were unable to correct a wheelie situation. Additional driving is planned for Sol 1818 (February 12, 2009) to mitigate the wheelie problem and continue the attempt to get onto Home Plate.

New battery modeling indicates a reduction in usable battery state of charge for the rover. However, on Sol 1812 (February 6, 2009), a small cleaning event improved the solar array's energy production by about 10 percent.

As of Sol 1816 (February 10, 2009), solar array energy production is 252 watt-hours, an improvement attributed to the cleaning event. Atmospheric opacity (tau) is 0.500, a slight improvement from the previous week. The solar-array dust factor improved to 0.282 (from the previous week's 0.256), meaning that 28.2 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health. Spirit's total odometry is 7,571.17 meters (4.70 miles).


sol 1803-1809, January 28 - February 03, 2009:  Finding Explanations

Activities on Spirit continued the investigation of anomalies from Sol 1800 (January 25, 2009) and Sol 1802 (January 27, 2009).

On Sol 1804 (January 29, 2009), the rover's flash memory, camera mast assembly, inertial measurement unit and mission clock were successfully checked. The rover's attitude was successfully established. On Sol 1805 (January 30, 2009), the accelerometers of the inertial measurement unit were investigated, and a small offset in the gravity vector was identified. This offset explains why the rover rejected the sun position found on Sol 1802 and explains that anomaly. Further investigation of this accelerometer offset is underway.

On Sol 1806 (January 31, 2009), the rover was commanded to drive and did so successfully. No symptoms from the Sol 1800 anomaly were observed. A careful review of flight software found the possibility that a cosmic-ray event could have caused the rover to not use the flash memory, and this would explain the behavior observed on Sol 1800. The flash memory retains information when the rover is powered down. Information that the rover does not save to flash memory is lost when the rover powers down between activity periods.

Spirit drove again on Sol 1809 (February 3, 2009). As of that sol, solar-array energy production is 202 watt-hours, barely enough to light a 100 watt bulb for two hours. Atmospheric opacity (tau) is 0.584, slightly higher than it was a week earlier. The dust factor on the solar array is 0.256, meaning that only 25.6 percent of the sunlight hitting the array penetrates the layer of dust to generate electricity. Spirit has resumed normal operations and is in good health.

As of Sol 1809 (February 3, 2009), Spirit's total odometry is 7,547.73 meters (4.69 miles).


sol 1797-1802, January 22-27, 2009:  Unexpected Behavior

Spirit has been revealing more evidence of silica in the terrain around "Home Plate." A drive planned for Sol 1797 (January 22, 2009) was delayed due to uplink problems, but was successfully completed on Sol 1798 (January 23, 2009). This 9-meter (30-foot) drive revealed light-toned material in the right-front wheel track.

Another drive was planned for Sol 1800 (January 25, 2009), but anomalous behavior occurred. Spirit did not record any telemetry during the time for which the drive had been commanded. A drive error flag was set. No explanation was developed to explain the absence of telemetry during this time. Subsequent imagery confirmed the rover did not move. A commanded activity to establish the rover's attitude on Sol 1802 (January 27, 2009) found the expected position of the sun outside of allowable limits, indicating some difficulty in understanding the rover attitude. Additional diagnostics were commanded to investigate this unexpected behavior.

As of Sol 1802 (January 27, 2009), Spirit's solar-array energy production is 200 watt-hours, enough to light a 100-watt bulb for two hours. Atmospheric opacity (tau) is 0.573, slightly higher than it was a week earlier. The dust factor is 0.255, meaning that only 25.5 percent of sunlight hitting Spirit's solar array penetrates the layer of accumulated dust to generate electricity. Otherwise, Spirit remains in good health. Spirit's total odometry is 7,540.67 meters (4.69 miles).


sol 1791-1797, January 15-22, 2009:  On the Move

Communication problems during the Martin Luther King, Jr. holiday led to the postponement of a drive planned for sol 1791 (Jan. 15, 2009) to sol 1793 (Jan. 17, 2009). Once the drive began, however, Spirit was able to go ahead with characterization of a rock target known as "Stapledon." Studies began with a stack of microscopic images taken at different focal lengths, then moved to compositional analysis using the alpha-particle X-ray spectrometer. On sol 1797 (Jan. 22, 2009), Spirit was to drive toward a prospective "on-ramp" to Home Plate, but a portion of the commands was corrupted during transmission and rejected by the rover. That particular drive is now planned for sol 1798 (Jan. 23, 2009). Also on sol 1797 Spirit was slated to take a deep sleep for the first time, as part of overall attempts to minimize power usage when not driving.

Future plans call for Spirit to drive south across Home Plate toward Goddard/Von Braun with all haste in order to reach the next "Winter Haven" before the end of the summer season.

Spirit is healthy and all subsystems are performing as expected as of the downlink of information from Mars for sol 1797 (Jan. 22, 2009). Solar-array energy is around 199 watt-hours (almost enough energy to light a 100-watt bulb for two hours). Tau (a measure of the amount of sunlight blocked by dust in the atmosphere) dropped to 0.536, slightly lower than last week. The dust factor, a measure of the amount of sunlight penetrating dust on the solar panels, is 0.2461, meaning that only about one-fourth of the sunlight reaching Spirit's solar arrays penetrates the layer of dust to generate electricity.

Sol-by-sol summary

In addition to making daily measurements of atmospheric darkness caused by dust, Spirit completed the following activities:

Sol 1791 (Jan. 15, 2009): Spirit completed a timed drive. At the end of the drive, Spirit took images with the hazard-avoidance and navigation cameras.

Sol 1792: Spirit took lossless-compression, full-color images, using all 13 filters of the panoramic camera, of a patch of material exposed in the wheel tracks called "Thunderbolt."

Sol 1793: Spirit completed another timed drive, acquired hazard-avoidance camera images, and took a post-drive, 5-x-1 tier of navigation-camera images.

Sol 1794: Spirit acquired full-color, lossless-compression images, using all 13 filters of the panoramic camera, of Thunderbolt.

Sol 1795: Spirit acquired a 3-by-1 tier of panoramic-camera images looking in the drive direction.

Sol 1796: Spirit checked for drift (changes with time) in the miniature thermal emission spectrometer, used the instrument to study the target called Robert Heinlein, unstowed the robotic arm, and acquired a 1-by-1-by-5 stack of stereo (3D) microscopic images of Stapledon. The rover placed the alpha-particle X-ray spectrometer on the target and, after relaying data to Odyssey, measured the elemental composition of Stapledon with the instrument.

Sol 1797: Spirit was slated to check for drift (changes with time) in the miniature thermal emission spectrometer, use the instrument to study the target called Robert Heinlein, stow the robotic arm, and drive, stopping mid-drive to take panoramic-camera images of Stapledon. At the end of the drive, the rover was to take images with the hazard-avoidance and navigation cameras. These events were rescheduled when a corrupted command sequence prevented them from taking place.

Sol 1798: Plans called for Spirit to take panoramic-camera images of a rock feature called "Mustang" along with spot images of the sky for calibration purposes.

Odometry

As of sol 1797 (Jan. 22, 2009), Spirit's total odometry was 7,531.60 meters (4.68 miles).


sol 1784-1790, January 08-14, 2009:  Spirit Guns the Engine

Spirit's activities during the past week involved finishing some remaining science tasks before starting the long drive to rock exposures nicknamed "Goddard/Von Braun." In addition, members of the science team debated whether to make a slight diversion to an interesting patch of soil before "hitting the highway".

The team finally decided to postpone Spirit's southward trek by a few sols (Martian days) to drive to, scuff, and use the alpha-particle X-ray spectrometer to determine the elemental composition of the soil patch. In the meantime, Spirit took images of rock targets called "Frank Russell," "El Dorado," "Jack Williamson," and "Stapledon2," as well as images detailing the stratigraphy (rock layers) of "Home Plate."

Future plans call for driving south and across Home Plate toward Goddard/Von Braun with all haste. Spirit needs to reach the next "Winter Haven" before the summer season, with its ample sunlight, ends.

Nicknames given to the rock targets are in honor of Eric Frank Russell (Jan. 6, 1905-Feb. 28, 1978), a British author best known for science-fiction novels and short stories; El Dorado, the legendary "City of Gold" imagined by Spanish conquistadors to exist somewhere in the Andes Mountains or the Amazon River Basin; John Stewart Williamson (April 29, 1908-Nov. 10, 2006), a U.S. writer often referred to as the "Dean of Science Fiction"; and William Olaf Stapledon (May 10, 1886-Sept. 6, 1950), a British philosopher and author of several influential works of science fiction.

Spirit is healthy and all subsystems are performing as expected as of the downlink of information from Mars for sol 1790 (Jan. 14, 2009). Solar-array energy is 185 watt-hours (100 watt-hours is the amount of energy needed to light a 100-watt bulb for one hour). Tau (a measure of the amount of sunlight blocked by dust in the atmosphere) dropped to 0.566. The dust factor, a measure of the amount of sunlight penetrating dust on the solar panels, is 0.2411, meaning that only about one-fourth of the sunlight reaching Spirit's solar arrays penetrates the layer of dust to generate electricity.

Sol-by-sol summary

In addition to making daily measurements of atmospheric darkness caused by dust, Spirit completed the following activities:

Sol 1784 (Jan. 8, 2009): Spirit calibrated the elevation of the mirror on the miniature thermal emission spectrometer, stared at the ground with the instrument, and acquired two 5-by-1 mosaics of post-drive, navigation-camera images. In the evening, the rover relayed data to NASA's Odyssey orbiter for transmission to Earth.

Sol 1785: Spirit acquired an 8-minute, time-lapse movie in search of dust devils with the navigation camera.

Sol 1786: Spirit checked for drift (changes with time) in the miniature thermal emission spectrometer, then used the instrument to survey the target called Eric Frank Russell. The rover acquired panoramic-camera images of El Dorado and super-resolution panoramic-camera images of Jack Williamson. Spirit took additional images with the navigation camera.

Sol 1787: Spirit measured atmospheric dust with the navigation camera as well as making the usual measurement with the panoramic camera. The rover took spot images of the sky for calibration purposes and images of the rover's tracks with the panoramic camera.

Sol 1788: Spirit checked for drift in the miniature thermal emission spectrometer and used the instrument to study Stapledon2 and the background of Stapledon2. The rover acquired panoramic-camera images of the rock layers in Home Plate.

Sol 1789: Spirit continued to take panoramic-camera images of the stratigraphy of Home Plate.

Sol 1790 (Jan. 14, 2009): Spirit completed runout activities while waiting for new instructions from Earth.

Odometry

As of sol 1790 (Jan. 14, 2009), Spirit's total odometry was 7,531.60 meters (4.68 miles).


sol 1776-1783, December 31, 2008 - January 07, 2009:  Descent of Spirit

Spirit has backed down off the steep edge of "Home Plate" where the rover spent its long Martian winter. After several unsuccessful attempts to drive forward up onto Home Plate, Spirit moved down off the slope with a 1.7-meter (5.6-foot) backward bump on Sol 1782 (January 6, 2009). This bump flattened out Spirit's tilt and improved solar-energy production.

As of Sol 1782 (January 6, 2009), Spirit's solar-array energy production is 192 watt-hours, an improvement from 160 watt-hours a week earlier. (It takes 100 watt hours to light a 100-watt bulb for an hour). Atmospheric opacity (tau) is 0.536, also an improvement. The dust factor on the solar array is 0.254, meaning that 25.4 percent of the sunlight hitting the solar array penetrates the layer of accumulated dust on the array. The rover is in good health. Spirit's total odometry is 7,531.60 meters (4.68 miles).

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