Since arriving at the rover's current location April 10, on its 807th sol, or Martian day, of exploration, Spirit's knowledge of its attitude relative to the Sun has drifted.
The NASA rover uses an onboard computer to keep track of attitude changes, but errors can accumulate in the measurement over time. On May 30, on sol 855, mission controllers at Jet Propulsion Laboratory transmitted an attitude update of 1.97 degrees to correct for the drift.
After the update, Spirit re-acquired images from the same location to allow the science team to target future observations accurately.
Meanwhile, Spirit continued to compile a 360-degree image controllers are calling the McMurdo panorama, and the rover removed another 2 millimeters of soil as part of a layer-by-layer soil study.
Sol 855 (May 30): Spirit completed a quick get-fine attitude, which is a procedure completed every couple of weeks to correct any error in the rover's knowledge of its attitude relative to the sun.
Spirit also took a 360-degree view of its surroundings with the navigation camera and a forward-looking view through the front hazard avoidance camera. The rover conducted remote sensing with the miniature thermal emission spectrometer during the overhead pass of the Mars Odyssey spacecraft.
Sol 856: Spirit acquired column 16 (a one-by-five mosaic) of the McMurdo panorama.
Sol 857: Spirit spent 80 minutes brushing away another 2 millimeters from the soil target controllers call Progress. This layer of the study is known as Progress 3.
Sol 858: Plans called for Spirit to take microscopic images of Progress 3, conduct remote sensing with the miniature thermal emission spectrometer during the afternoon overhead pass of the Odyssey spacecraft, and take two panoramic-camera images during the Martian sunset.
Sol 859 (June 3): Plans called for Spirit to acquire column 17 (a one-by-three mosaic) of the McMurdo panorama.
As of sol 857, on June 1), Spirit's total odometry remained at 6,876.18 meters (4.27 miles).
Copyright 2006 by Space Daily, Distributed United Press International
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