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RE: The Opportunity rover

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NASA ROVER NEARS MARTIAN VICTORIA BOWL GOAL

NASA's Mars rover Opportunity is closing in on what may be the grandest overlook and richest science trove of its long mission.

During the next two weeks, the robotic geologist is likely to reach the rim of a hole in the Martian surface wider and deeper than any it has visited. The crater, known as "Victoria," is approximately one-half mile wide and 230 feet deep.
Images from NASA's Mars Global Surveyor orbiter show the crater walls expose a stack of rock layers approximately 100 to 130 feet thick. Opportunity will send back its initial view into the crater as soon as it gets to the rim. Scientists and engineers will use Opportunity's observations from points around the rim to plot the best route for entering the crater.

"Victoria has been our destination for more than half the mission. Examination of the rocks exposed in the walls of the crater will greatly increase our understanding of past conditions on Mars and the role of water. In particular, we are very interested in whether the rocks continue to show evidence for having been formed in shallow lakes" - Ray Arvidson of Washington University, St. Louis. Arvidson is deputy principal investigator for Opportunity and its twin rover, Spirit.

The NASA rovers have been exploring landscapes on opposite sides of Mars since January 2003. Their prime missions lasted three months. Both are still investigating Mars' rocks, soils and atmosphere after more than 30 months. Opportunity works in a region where rock layers hundreds of yards in thickness cover older, heavily cratered terrain.

"We have a fully functional vehicle with all the instruments working. We're ready to hit Victoria with everything we've got" - Byron Jones, a rover mission manager at NASA's Jet Propulsion Laboratory, Pasadena, California.

Though it's still winter in Mars' southern hemisphere, days have begun getting longer again, and Opportunity's power supply from its solar panels is increasing daily. During its first two months on Mars, Opportunity examined a one-foot stack of rock layers at its landing site inside "Eagle Crater" and found geological evidence that water had flowed across the surface long ago.
The rover spent the next nine months driving to and exploring a larger crater, "Endurance." There it examined a stack of exposed layers 23 feet thick. Over the drive from Endurance to Victoria, the rocks tell a history of shallow lakes, drier periods of shifting dunes and groundwater levels that rose and fell. Minerals indicate the ancient water was very acidic.
The much thicker stack of revealed rock layers at Victoria beckons.

"We want to examine the thick section of rocks exposed on the walls in Victoria crater to understand whether the environment that produced these materials was similar to the environment recorded in the rocks that we have seen so far. Is there a record of a different type of deposition? Was there a wet environment that was less acidic, perhaps even more habitable? Where do the layers from Endurance fit in this thicker sequence?" - Ray Arvidson.

NASA's Mars Reconnaissance Orbiter reached Mars in March 2006. It will begin its primary science phase in November, offering higher resolution images and mineral mapping than have been possible with previous orbiters.
Victoria will be one target for the orbiter.

"By combining the data from Opportunity and Mars Reconnaissance Orbiter, we'll be able to do some fantastic coordinated analysis" - Ray Arvidson.

Such analysis will enhance the science return of both missions and aid in interpreting orbiter data taken of potential landing sites for future missions elsewhere on Mars.

"It's an amazing accomplishment that Spirit and Opportunity have completed the equivalent of 10 prime missions. Each of them shows some signs of aging, though. We can't say how long the rovers will last, but we will push to get the best possible science out of these national treasures as long as they keep operating. Victoria could very well be the most productive and exciting science of the entire mission"- John Callas, rover project manager at JPL.

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OPPORTUNITY UPDATE: Inching Closer to 'Victoria' - sol 920-927, September 1, 2006:

Opportunity is healthy and still 218 metres from "Victoria Crater." Over the weekend, the rover's shoulder azimuth joint stalled as Opportunity was trying to start measurements on a trench it dug on Sol 919 (Aug. 25, 2006). Consequently, all weekend arm activities were aborted, but remote science activities were executed as planned.
Beginning on Sol 923, rover arm diagnostic measurements were taken as well as some remote sensing science. Results from the diagnostics revealed neither cause nor any damage to the stalled joint. On Sol 924, the arm performed flawlessly as Opportunity successfully completed the activities originally planned for Sol 920. On Sols 925, 926 and 927 Opportunity collected more arm diagnostics (to ensure the stow before drive would go smoothly) as well as completing all arm activities originally planned over the weekend.

Sol-by-sol summaries:

Sol 920 (Aug. 26, 2006): Opportunity did a miniature thermal emission spectrometer observation and other activities were aborted due to the arm stall.

Sol 921: The rover took a panoramic camera image.

Sol 922: Opportunity used its panoramic camera and miniature thermal emission spectrometer.

Sol 923: The rover conducted arm diagnostics and took panoramic camera and miniature thermal emission spectrometer observations.

Sol 924: Completing the activities originally planned for sol 920, Opportunity took a microscopic image and did an alpha particle X-ray spectrometer observation.

Sol 925: The rover continued to do arm diagnostics and completed a Mössbauer spectrometer observation - a completion of sol 921's originally planned activities.

Sol 926: Opportunity continued to do arm diagnostics and completed activities originally planned for sol 922 by taking microscopic images and using the Mössbauer spectrometer.

Sol 927: On this sol, the rover used its Mössbauer spectrometer.

As of sol 925 (August 31, 2006), Opportunity's total odometry was 9,023.70 metres.

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Opportunity - Sol 900 to 904
Beagle Crater

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Credit nasa/JPL

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OPPORTUNITY UPDATE: Closer and Closer to 'Victoria' - sol 913-919, August 25, 2006:

Opportunity is healthy and located only 218 metres from the rim of "Victoria Crater." Opportunity's odometer clicked past the 9-kilometre mark as it drove 237.81 metres during the week. The terrain within the annulus, or ring, of material surrounding Victoria is homogeneous and flat, which is favourable for long drives. The team planned a trenching activity for sol 919 (Aug. 25, 2006) to prepare for a robotic arm campaign during the weekend.

Sol-by-sol summaries:

Sol 913 (Aug. 18, 2006): Opportunity used its panoramic camera to conduct a 13-filter systematic foreground observation, gathered a systematic foreground raster with the miniature thermal emission spectrometer and used the navigation camera in support of that spectrometer. The rover measured the atmosphere's clarity (a measurement called "tau") with the panoramic camera and used the miniature thermal emission spectrometer for observations of targets "Tenerife" (a boulder) and "Tenerife BG" (soil near the boulder).

Sol 914: Opportunity drove 71.72 metres then took images from its new position with the navigation camera and the panoramic camera. The rover also conducted a test to aid the design effort for NASA's 2009 Mars Science Laboratory. Opportunity's navigation camera took an image of the sunset. The image was designed to help in development of an algorithm for determining the rover's position using the sun and the time of day. The miniature thermal emission spectrometer observed sky and ground during the afternoon communication-relay pass of NASA's Mars Odyssey orbiter.

Sol 915: The rover conducted monitoring of dust on the panoramic mast assembly, used the panoramic camera to survey clasts (rock fragments) and used the miniature thermal emission spectrometer to observe sky and ground.

Sol 916: The rover drove backwards for 88.82 metres.

Sol 917: Opportunity drove backwards 77.27 metres and took mosaics of images with the navigation camera. Before the Mars Odyssey pass, the rover took a panoramic camera tau measurement. During the orbiter's pass, the miniature thermal emission spectrometer conducted a foreground stare. The rover also took a panoramic camera 13-filter foreground image.

Sol 918: Opportunity did untargeted remote sensing, including: a panoramic camera albedo measurement, a navigation camera rear-looking mosaic, a front hazard avoidance camera image for potential robotic-arm work, and a miniature thermal emission spectrometer seven-point sky and ground observation. The rover also took a panoramic camera tau measurement before the first of two Odyssey passes and a miniature thermal emission spectrometer sky and ground observation during the first Odyssey pass.

Sol 919: Plans call for Opportunity to take a panoramic camera image of the location selected for trenching, then to advance 2.3 metres and use a wheel to dig the trench, pausing to take images. Next in the plan are navigation camera mosaics in the forward and rear directions, then observations of sky and ground with the miniature thermal emission spectrometer during the Odyssey pass.

As of sol 918 (August 24, 2006), Opportunity's total odometry was 9,015.19 metres.

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Opportunity Sol 917

Right Panoramic Camera Non-linearised Full frame EDR acquired on Sol 917 of Opportunity's mission to Meridiani Planum at approximately 14:28:13 Mars local solar time, camera commanded to use Filter 2 (754 nm).

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Credit NASA/JPL/Cornell

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Opportunity Sol 912

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OPPORTUNITY UPDATE: Opportunity Observes 'Isabela' - sol 907-912, August 18, 2006:

Opportunity is healthy and on the road to "Victoria Crater." Spirit drove 35.67 meters from "Beagle Crater" to a small sand dune, or ripple, to examine the dune with the robotic arm. The ripple study included observations with the microscopic imager, two alpha particle X-ray spectrometer integrations, and two observations with the miniature thermal emission spectrometer.

Sol-by-sol summaries:

Sol 907 (Aug. 12, 2006): Opportunity drove 31.4 meters away from Beagle Crater toward a ripple.

Sol 908: Opportunity performed a navigation camera experiment and made observations with the miniature thermal emission spectrometer.

Sol 909: Opportunity drove 4.27 metres and used the robotic arm on the ripple. It also took images with the panoramic camera, navigation camera and hazard-avoidance cameras.

Sol 910: Opportunity took pictures of targets informally named "Isabela" and "Marchena" with the microscopic imager. The rover also took measurements of Marchena with the alpha particle X-ray spectrometer.

Sol 911: Opportunity moved the robotic arm out of the way and took pictures of the area where it would later use the alpha particle X-ray spectrometer. Opportunity made observations of targets informally named "Pinzon" and "Pinta" with the miniature thermal emission spectrometer. Opportunity did a reading of Isabela with the alpha particle X-ray spectrometer after the Odyssey communications pass.

Sol 912 (Aug. 17, 2006): The plan is for Opportunity to stow the robotic arm and drive toward Victoria Crater at a heading of 163 degrees.

Odometry:
As of sol 911 (Aug. 16, 2006), Opportunity's total odometry was 8723.38 metres.

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Closeup of dune ripple on Victoria apron on Meridiani Plain, Mars.
Taken by Opportunity August 15, 2006 ( Sol 909).

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OPPORTUNITY UPDATE: Opportunity Recovers from Brief Operational Anomaly - sol 900-906, August 11, 2006:

While Opportunity was collecting images with the panoramic camera on the rover's 902nd Martian day, or sol (Aug. 7, 2006), a spacecraft anomaly at 11:19 a.m. local solar time caused the rover's fault protection software to interrupt operations, place the rover in a safe state, and reboot the flight software. Upon waking up after the reset, Opportunity flagged the positions of the high-gain antenna and pancam mast assembly as unknown. Opportunity then remained in automode (meaning the rover did not attempt to execute a master sequence of activities for the day).
The rover's handlers transmitted instructions to Opportunity to re-establish the position of the high-gain antenna on sol 903 (Aug. 8, 2006) and the position of the pancam mast assembly on sol 904 (Aug. 9, 2006). Sols 903 and 904 were primarily dedicated to retrieving diagnostic information. On sol 904, Opportunity successfully reacquired the sequence of panoramic camera images that had been terminated by the fault and collected scientific data. As of sol 905 (Aug. 10, 2006), Opportunity was completely restored to normal operations. Opportunity remains healthy and engineers have not found a credible explanation for what caused the anomaly.
Before the fault, Opportunity had been working on a campaign of science observations of the area around "Beagle Crater," including an analysis of laminated ripples using instruments on the rover's robotic arm. Opportunity has resumed work on those observations.

Sol-by-sol summaries:

Sol 900 (Aug. 5, 2006): Opportunity made tau observations (measurements of dust opacity in the atmosphere) using the panoramic camera and completed two image mosaics of Beagle Crater with the panorama camera: a four-by-four mosaic known as "Beagle Pan B" and a two-by-four mosaic known as "Beagle Pan D." Opportunity acquired images of a target known as "Fernandina" using all 13 filters of the panoramic camera and made observations of a target known as "Darwin" with the miniature thermal emission spectrometer. The rover acquired morning panoramic camera images of targets "Camarhynchus" and "Cactospiza" and a portion of the sky. Opportunity checked for drift (changes with time) in the miniature thermal emission spectrometer and surveyed the sky and ground with the same instrument.

Sol 901: Opportunity made tau observations using the panoramic camera and completed two image mosaics of Beagle Crater with the panorama camera: a four-by-four mosaic called "Beagle Pan A" and a four-by-four mosaic called "Beagle Pan C." Opportunity acquired images of a target known as "Floreana" using all 13 filters of the panoramic camera. The rover acquired miniature thermal emission spectrometer data from Camarhynchus and a target called "Geospiza." Opportunity acquired panoramic images of a target known as "Platyspiza."

Sol 902: Opportunity made tau observations with the panoramic camera. At 11:19 a.m. local solar time, a spacecraft fault put the rover in a safe state.

Sol 903: Opportunity ran engineering sequences to recover from the previous day's fault responses and retrieve diagnostic data.

Sol 904: Opportunity acquired stereo images with the navigation camera without activating the pancam mast assembly and ran engineering sequences to complete the rover's recovery from the fault that occurred on sol 902. Opportunity took images of the calibration target for the panoramic camera and re-acquired "Beagle Part 5," the sequence of images that was terminated by the fault on sol 902.

Sol 905: Opportunity made tau observations using the panoramic camera, acquired a two-by-one mosaic of Darwin with the panoramic camera, and acquired images of Geospiza using all 13 filters of the panoramic camera. The rover scanned for clouds using the navigation camera's wide field of view. Opportunity also checked for drift in the miniature thermal emission spectrometer and surveyed the sky and ground with the same instrument.

Sol 906 (Aug. 11, 2006): Plans called for Opportunity to take tau measurements with the panoramic camera, monitor dust on the pancam mast assembly using the miniature thermal emission spectrometer, survey the ground and sky at various elevations using the miniature thermal emission spectrometer, and collect reference data from the calibration target for the thermal emission spectrometer. During this procedure, the rover was to check for drift (changes over time) in measurements from the instrument.

Odometry:
As of sol 897 (Aug. 2, 2006), Opportunity's total odometry was 8,687.56 metres.