OPPORTUNITY UPDATE: Stutter Stepping to El Capitan
sol 25, Feb 19, 2004
On sol 25, which ended at 11:38 p.m. Wednesday, February 18, PST, Opportunity used the microscopic imager and alpha particle x-ray spectrometer to study the chemical makeup of the wall and floor area within the rover-made trench. Due to time constraints, Opportunity was unable to take a picture of the heat shield in the distance. Sol 25’s wake-up music was “Fascination” by Human League. The plan for sol 26, which will end at 12:18 a.m. Friday, PST, is to back away from the trench, obtain one grand finale Moessbauer spectrometer reading of the trench, pick up and stow the rover arm, then turn and drive 9 meters (30 feet) to the El Capitan area. Opportunity will make a few intentional “stutter steps” on its way to El Capitan, stopping to take a few front hazard avoidance camera images and navigation camera images to plan for final approach and robotic arm activities. Opportunity will stop a couple of meters (about 6 or 7 feet) short of El Capitan to take images with its panoramic camera and gather science measurements with its miniature thermal emission spectrometer. On sol 27, Opportunity will make a short, closer approach to El Capitan to poise itself to use the rock abrasion tool and other instruments on the rover arm.
SPIRIT UPDATE: Halfway Through
sol 46, Feb 19, 2004
Sol 46, completed at 11:17 a.m. February 19, 2004 PST, marks the halfway point of Spirit’s primary surface mission – sols 2 through 91. Spirit began this momentous morning by doing some remote sensing of the crater rim and imaging the surrounding soil with the panoramic camera and miniature thermal emission spectrometer. After all this work, Spirit took a break with a nap lasting slightly more than an hour. After waking, Spirit continued its observations of the ground and sky with the miniature thermal emission spectrometer. At about 1:34 p.m. Mars Local Solar Time, Spirit found itself analyzing a patch of the atmosphere with the miniature thermal emission spectrometer at the same time that Mars Global Surveyor’s thermal emission spectrometer was looking down through the same chunk of atmosphere. This concurrent observation will enable a more thorough understanding of martian atmospheric conditions. Spirit’s afternoon activities began at about 4:00 p.m. Mars Local Solar Time after the Mars Global Surveyor pass. Spirit was expected to take stereo microscopic images of the target “Trout” in Laguna Hollow. This is the first time the microscopic imager will take pictures at Gusev Crater without the Moessbauer instrument first touching the surface of the soil. The observation will provide pictures of undisturbed soil. After this, Spirit will perform a calibration activity by imaging a location in the sky with the microscopic imager and the navigation camera simultaneously. Spirit’s day will stretch into the night this sol with an overnight Moessbauer spectrometer integration. After a brief sleep, Spirit will wake at about 2:00 a.m. Mars Local Solar time on sol 47 to end the integration, collect the data and turn on the arm heaters. It will prepare for changing the tool from the Moessbauer to the alpha particle x-ray spectrometer, and begin observations with the new tool. Finally, the rover will leave the alpha particle x-ray spectrometer powered on and go back to sleep around 2:30 a.m. Mars Local Solar time. On the morning of Sol 47, which will end at 11:57 a.m. February 20, 2004 PST, the plan is for Spirit to end the alpha particle x-ray observation and collect that data, and then perform some early mini-thermal emission spectrometer soil properties observations.