* Astronomy

OPPORTUNITY UPDATE: Opportunity Manoeuvres Around Steeper Slopes in "Victoria Crater" - sol 1375-1381, Dec 17, 2007:

Opportunity is now in the process of driving to the third band of light-coloured rocks that circumvent "Victoria Crater" beneath the rim. Scientists had initially planned to have the rover head directly downhill to a rock target nicknamed "Ronov," within the band known as "Lyell." They selected an alternate rock exposure, dubbed "Newell," when engineers determined that the original drive route would tilt the rover 25 degrees, somewhat higher than desired. The estimated tilt along the new route is a much gentler 20 degrees but the drive is somewhat more complex and required two days of planning.
During the past week, Opportunity completed scientific investigation of the second band of rocks, known as "Smith," with an analysis of elemental chemistry and iron-bearing minerals beneath the surface of a rock exposure labelled "Smith2." To do this, the rover collected data with the alpha-particle X-ray spectrometer Mössbauer spectrometer, respectively.
If next week's planned drive goes as anticipated and closer inspection of Newell deems it to be an acceptable target, Opportunity is likely to stay at the new location for several weeks collecting data. Scientists plan to have the rover conduct a complete campaign of studies with the alpha-particle X-ray and Mössbauer spectrometers, microscopic imager, rock abrasion tool, and on-board cameras.
During the planned drive, Opportunity will complete a "Get Quick Fine Attitude," a procedure for determining the rover's position relative to the changing position of the Sun. This activity recalibrates the inertial measurement unit and eliminates tiny errors that accumulate over time in pointing the antenna.
Opportunity is healthy and all subsystems are operating as expected. The latest available power readings, taken on Martian day, or sol, 1379 (Dec. 10, 2007), show solar energy levels at a robust 601 watt-hours, enough to light a 100-watt bulb for 6 hours.

Sol-by-sol summary:
In addition to morning uplinks directly from Earth via the rover's high-gain antenna, evening downlinks to Earth via the Odyssey orbiter at UHF frequencies, and standard measurements of atmospheric opacity caused by dust using the panoramic camera, Opportunity completed the following activities:

Sol 1375 (Dec. 6, 2007): Opportunity placed the alpha-particle X-ray spectrometer on Smith2 and, after the overpass of the Odyssey orbiter, collected data with the instrument. The next morning, when the Sun powered the solar arrays, Opportunity scanned the sky for clouds with the navigation camera.

Sol 1376: Opportunity conducted extensive measurements of atmospheric dust and scanned the sky for clouds with the navigation camera.

Sol 1377: Opportunity placed the Mössbauer spectrometer on Smith 2 and collected data with the instrument. Opportunity acquired calibration images and part 1 of a panoramic view of the rover deck that involved 23 pointings with the panoramic camera. The rover surveyed the sky at high sun with the panoramic camera and scanned the sky for clouds with the navigation camera.

Sol 1378: Opportunity re-started the Mössbauer spectrometer and continued data collection from Smith2. The rover acquired part 2 of a panoramic view of the rover deck, completing 24 pointings of the panoramic camera. Opportunity surveyed and took spot images of the sky for calibration purposes using the panoramic camera.

Sol 1379: Opportunity re-started the Mössbauer spectrometer and resumed data collection from Smith2. The rover then acquired part 3 of the panoramic view of the spacecraft deck, a series that entailed 29 pointings of the panoramic camera. In the morning, Opportunity scanned the sky for clouds with the navigation camera and monitored dust on the rover mast assembly.

Sol 1380: Opportunity scanned the sky for clouds with the navigation camera.

Sol 1381 (Dec. 12, 2007): Opportunity surveyed the sky at low sun with the panoramic camera and measured argon gas in the Martian atmosphere with the alpha-particle X-ray spectrometer. The rover searched for clouds in the morning sky with the navigation camera.

Odometry:
As of sol 1379 (Dec. 5, 2007), Opportunity's total odometry remained at 11,584.32 meters, where the rover has been stationed since the last drive on Sol 1329 (Oct. 20, 2007).

OPPORTUNITY UPDATE: Opportunity Grinds into Rock in "Victoria Crater" - sol 1368-1374, Dec 10, 2007:

Opportunity spent part of the past week carefully grinding a hole into the surface of a light-coloured ring of rock inside "Victoria Crater" known as "Smith," despite the previous loss of encoders that enabled two of the motors of the rock abrasion tool to operate under control of the tool's flight software. The endeavour was successful, with the rover grinding to a depth of about 1 millimetre - about the thickness of a dime - deep enough to allow measurement of the rock chemistry beneath the surface. The rover is healthy and all systems are normal.
Rover engineers devised and tested a novel approach for operating the rock abrasion tool that enabled it to locate the surface independent of the encoders on the grind and revolve motors. Opportunity implemented a "Grind Scan" procedure to find the surface on sol 1368 (Nov. 29, 2007). Two days later, on sol 1370 (Dec. 1, 2007), Opportunity ground into the surface. Though the science team originally planned to have the tool grind 2 millimetres into the surface, the contact switches that engaged when the tool was placed on the rock released, likely due to vibration under a light pre-load of the RAT against the target. This release caused the grinding to halt at half the planned depth. Images sent to Earth showed that even though the hole was somewhat unusual in appearance as the result of a bent wire brush, it was suitable for analysis using the alpha-particle X-ray spectrometer.
Images of the sky taken on sol 1373 (Dec. 4, 2007) showed that some of the dust had cleared from the lens of Opportunity's microscopic imager.
Working with NASA's Mars Reconnaissance Orbiter, Opportunity completed the second of two communications tests verifying the relay capability of the orbiter in preparation for the Phoenix mission, now en route to Mars. The second round of testing involved the use of the Electra telecommunications package on the orbiter to measure the distance and speed of incoming spacecraft relative to Mars based on UHF radio signals and to measure the location of a landed spacecraft on the surface of Mars. Opportunity provided useful data for both measurements - using the "relative window" mode and the "fixed window" mode.
Opportunity continued to generate abundant solar power levels of 638 watt-hours, enough energy to light a 100-watt bulb for more than 6 hours, measured on Martian day, or sol, 1373 (Dec. 4, 2007). Scientists planned to have the rover finish up work on Smith and then descend to the last of three light-coloured rings of rock. This final ring is known as "Lyell."

Sol-by-sol summary:
In addition to morning uplinks directly from Earth via the rover's high-gain antenna, evening downlinks to Earth via the Odyssey orbiter at UHF frequencies, and standard measurements of atmospheric opacity caused by dust using the panoramic and navigation cameras, Opportunity completed the following activities:

Sol 1368 (Nov. 29, 2007): Opportunity completed the "Grind Scan" procedure to find the rock surface to be ground, tested UHF communications with the Mars Reconnaissance Orbiter, and acquired panoramic camera images, including part 5 of a panorama of a light-toned exposure of rock known as "Pettijohn." Upon awakening the next morning, Opportunity scanned the sky for clouds using the navigation camera.

Sol 1369: Opportunity took extensive measurements of atmospheric dust and searched for clouds using the navigation camera.

Sol 1370: Opportunity ground into the surface of the rock target known as "Smith2," acquired images of the sky with the microscopic imager to monitor dust on the instrument lens, and measured argon gas in the Martian atmosphere with the alpha-particle X-ray spectrometer. The next morning, the rover scanned the sky for clouds using the navigation camera.

Sol 1371: Opportunity acquired full-colour images, using all 13 filters of the panoramic camera, of Smith2. The rover acquired additional images with the panoramic camera, including part 6 of the Pettijohn panorama.

Sol 1372: Opportunity surveyed the sky at high sun with the panoramic camera, took extensive measurements of atmospheric dust, scanned the sky for clouds with the navigation camera, and took spot images of the sky to calibrate the panoramic camera.

Sol 1373: Opportunity acquired stereo, microscopic images of Smith2, surveyed the rock abrasion tool and the grinding bit with the panoramic camera, and took more full-colour images, using all 13 filters of the panoramic camera, of Smith2. Opportunity took images of the sky with the microscopic imager to characterize dust on the lens and scanned the sky for clouds with the navigation camera.

Sol 1374 (Dec. 5, 2007): In addition to measuring atmospheric dust, Opportunity scanned the sky for clouds using the navigation camera, surveyed the sky with the panoramic camera, and took thumbnail images of the sky with the panoramic camera.

Odometry:
As of sol 1374 (Dec. 5, 2007), Opportunity's total odometry remained at 11,584.32 metres, where the rover has been stationed since the last drive on Sol 1329 (Oct. 20, 2007).

OPPORTUNITY UPDATE: Multi-Tasking Rover Supports Multiple Missions - sol 1361-1367, Nov 30, 2007:

Opportunity continues to investigate the rock exposure known as "Smith2" in the second of three bathtub ring-like layers of rock inside "Victoria Crater" as well as test communications for Phoenix, NASA's next mission to Mars. The rover is healthy and all subsystems are normal.
On Sol 1361 (Nov. 22, 2007), Opportunity performed diagnostic tests of the shoulder joint that controls side-to-side movement of the robotic arm, known as Joint 1. The joint had stalled on Sol 1359 (Nov. 20, 2007) while the rover was taking measurements with the microscopic imager. The tests revealed no anomalous readings. Opportunity acquired the rest of the microscopic images of Smith 2 on Sol 1366 (Nov. 27, 2007).
After the diagnostic tests, Opportunity studied the elemental chemistry of Smith2 with the alpha-particle X-ray spectrometer and the composition and abundance of iron-bearing minerals in the outcrop with the Mössbauer spectrometer.
Working with NASA's Reconnaissance Orbiter, Opportunity successfully tested UHF radio transmissions in support of entry, descent, landing, and surface operations of the Phoenix mission, now en route to the red planet. On Sol 1367 (Nov. 28, 2007), the rover and the orbiter used the international standard known as the Proximity-1 protocol for spacecraft data transfers.
Phoenix is expected to arrive at Mars on May 25, 2008. Radio signals from Phoenix may also be receivable directly via the Robert C. Byrd Green Bank Telescope in Virginia, the world's largest, fully steerable radio telescope.

Sol-by-sol summary:
In addition to morning uplinks directly from Earth via the rover's high-gain antenna, evening downlinks to Earth via the Odyssey orbiter at UHF frequencies, and standard measurements of atmospheric opacity caused by dust using the panoramic and navigation cameras, Opportunity completed the following activities:

Sol 1361 (Nov. 22, 2007): Opportunity performed diagnostic tests of the robotic arm, placed the alpha-particle X-ray spectrometer on the target known as Smith2, and collected 6 hours of data with the instrument. The rover went into a mini-deep sleep and upon awakening the next morning, scanned the sky for clouds with the navigation camera.

Sol 1362: Opportunity placed the Mössbauer spectrometer on Smith2 and spent 10 hours collecting data with the instrument. The rover went into a mini-deep sleep and the next morning, searched for clouds with the navigation camera.

Sol 1363: Opportunity restarted the Mössbauer spectrometer and collected 12 hours of compositional data with the instrument. The rover acquired a mosaic of images that are part of a panoramic view of a light-toned exposure of sedimentary rock known as "Pettijohn." The next morning, the rover scanned the sky for clouds with the navigation camera.

Sol 1364: Opportunity restarted the Mössbauer spectrometer and collected an additional 11 hours of compositional data from Smith2 with the instrument. The rover scanned the sky for clouds with the navigation camera.

Sol 1365: Opportunity restarted the Mössbauer spectrometer and collected 12 hours of compositional data from Smith2 with the instrument. The rover acquired "Part 3" of the panoramic-camera mosaic of Pettijohn.

Sol 1366: Opportunity switched tools from the Mössbauer spectrometer to the microscopic imager and acquired microscopic images looking up at the sky for calibration purposes. The rover also took external images of the microscopic imager with the hazard avoidance cameras. Opportunity then acquired stereo microscopic images of Smith2. Opportunity switched tools from the microscopic imager to the rock abrasion tool and acquired "Part 4" of the Pettijohn panorama. The next morning, Opportunity scanned the sky for clouds with the navigation camera, surveyed the horizon with the panoramic camera, and took spot images of the sky with the panoramic camera.

Sol 1367 (Nov. 28, 2007): Plans called for Opportunity to scan the sky for clouds with the navigation camera and take thumbnail images of the sky with the panoramic camera.

Odometry:
As of sol 1366 (Nov. 27, 2007), Opportunity's total odometry remained at 11,584.32 metres, where the rover has been stationed since the last drive on Sol 1329 (Oct. 20, 2007).

Image taken of the wall of Duck bay by the Opportunity rover on November 19th, 2007 (Sol 1358)


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Credit NASA