Update: Spirit and Opportunity

SPIRIT UPDATE: Spirit investigating 'Tetl.' - sol 263-271, October 11, 2004

After working on Mars for three times as long as its primary three-month mission, Spirit is healthy and currently investigating the rock called "Tetl" in the "Columbia Hills." In the language of the ancient Mayans, tetl means stone.

On sol 263, Spirit successfully drove approximately 7 meters (23 feet) and acquired images to build a digital elevation map of the hills. This put Spirit on the south side of a 2-meter-diameter (7-foot-diameter) depression, with Tetl on the opposite side.

On sol 264, Spirit drove about 4 meters (13 feet) around the edge of the depression to keep the rover's solar panels (which are the rover's main power source) tilted toward the Sun. Since the Sun moves low across the northern sky over Gusev Crater at this time of year, rover planners are attempting to keep the solar panels tilted toward the north. The drive included use of the five-wheel mode to minimize use of the sticky right front wheel, which inefficiently pulls too much power when it is activated. Spirit also gathered additional about potential science targets, using the miniature thermal emission spectrometer and panoramic camera at the end of the rover's robotic arm.

On sol 265, Spirit attempted to approach Tetl, but the drive ended early because the flight software detected that a steering brake control function did not work. Remote sensing data was still acquired.

On sol 266, with an ongoing investigation of the steering anomaly, no further driving was planned. Several targets in front of the rover were selected for the alpha particle X-ray spectrometer and Mössbauer spectrometer. Spirit completed alpha particle X-ray spectrometer readings on two different locations.

On sol 267, Spirit successfully acquired remote sensing data and moved its robotic arm to put the alpha particle X-ray spectrometer at a third position during the day and a fourth position overnight.

On sol 268, Spirit acquired additional remote sensing data and performed a tool change to the Mössbauer spectrometer, then started an overnight integration with that instrument.

On sol 269, Spirit continued the Mössbauer spectrometer integration and performed a diagnostic test on the steering brake. The test indicated that there was no problem with the commanding process at that time.

On sol 270, Spirit acquired remote sensing data, stowed its arm, and ran another steering diagnostic test. The cause of the steering brake issue has not been identified, but tests indicate that electronics related to the brake function and the overall steering capabilities of Spirit are healthy. Engineers are proceeding with normal operations, including mobility.

On sol 271, which ended on Oct. 7, Pacific Time, Spirit successfully drove approximately 2 meters (6.6 feet). This put Tetl within reach of the robotic arm. After the drive, Spirit used its navigation camera to view the scene from the rover's new location.

Spirit has driven a total of 3,641 meters (about 2.3 miles) since landing nine months ago.

Future plans for Spirit include more intense investigations of Tetl and a 20-meter (66-foot) drive to a target called "Machu Picchu."

Spirit Update Archive

OPPORTUNITY UPDATE: Working towards 'Wopmay' - sol 245-250, October 13, 2004

Opportunity is in excellent health. The current pattern is to use the deep-sleep mode every second night, and to support an early morning Odyssey communications pass on the non-deep-sleep nights. Opportunity is experiencing good solar exposure, averaging more than 660 watt-hours per sol from the solar arrays. The rover is poised for final approach to "Wopmay," a fascinating creviced rock with a brain-like appearance.

Sol details:

Sol 245 was a restricted sol. Opportunity could perform only remote sensing. The rover took images in all directions with its navigation camera. It used its miniature thermal emission spectrometer for sky and ground observations. Then it went into deep sleep for the night of sol 245 into the morning of sol 246.

Sols 246 through 248 were planned in a single planning cycle as part of our 5-day-a-week schedule. The uplink team accomplished a Herculean task, successfully completing and uplinking three science-intensive sol plans despite some issues encountered during the day.

Opportunity began sol 246 by placing the Mössbauer spectrometer and starting a long reading with it on a target called "Void." While collecting the Mössbauer data, Opportunity also performed two hours of observations with its panoramic camera and its miniature thermal emission spectrometer. The Mössbauer integration was paused just before the afternoon communication session with Mars Odyssey. Deep sleep was disabled so that Opportunity could support an early morning communications session on sol 247 and restart the Mössbauer integration.

Sol 247 was day two of the long Mössbauer integration; the integration ran throughout the sol until early evening, at which time Opportunity again paused and entered deep sleep overnight. During the day, Opportunity also completed a series photometric observations with its panoramic camera.

On sol 248 Opportunity exited deep sleep and restarted the Mössbauer integration. During pre-uplink science activities in the early morning, the rover completed a sky observation pattern that planners call an itty-bitty cloud movie. In the martian afternoon, Opportunity ended the long Mössbauer integration and turned the tool turret on its arm to place the alpha particle X-ray spectrometer on Void. The X-ray instrument did not start taking data until early the next morning. Opportunity did not go into deep sleep overnight. Instead, it used an early morning Odyssey communications session and immediately afterwards started the alpha particle X-ray spectrometer integration.

Opportunity completed the alpha particle X-ray spectrometer integration on the morning of sol 249. The rover then performed a series of microscopic imaging activities, stowed the instrument deployment device and began driving toward its next target, Wopmay. The 19.98-meter (about 66-foot) drive went well, but with more slippage than expected. At the end of the drive, the nearest visible face of Wopmay was only 2 meters (about 7 feet) from the center of the rover; far enough not to have been a hazard during the drive, but closer than was predicted. Slip estimates indicate radial slippage as high as 64 percent. Opportunity used deep sleep overnight on sol 249.

On sol 250, which ended on Oct. 7, Opportunity performed the first part of a planned two-sol approach to Wopmay. This nearly 7-meter (23-foot) drive went well. The end of the drive incorporated conditional arcs to be executed only if the rover was in the appropriate position. The drive put the rover in very good position for the final approach on sol 251.

Total odometry after sol 250 puts Opportunity just over the one-mile mark: 1,611.99 meters (1.0016 mile)!

Opportunity Update Archive