Pathfinder's 10.5-kilogram (23-pound) rover called Sojourner stalled today during the last stretch of its journey to a rock nicknamed Mermaid, but was quick to recover and prepare for completion of the traverse tomorrow.
Data returned this morning from the Sagan Memorial Station indicated that the rover's left front wheel stalled during the third of four waypoint maneuvers. Waypoints are navigational instructions -- consisting of x- and y-axis coordinates -- used by the rover to travel from one rock to another. To complete today's traverse to the rock nicknamed Mermaid, for instance, the rover had to make four short trips based on four sets of waypoint coordinates. Its wheel jammed during the third segment of the journey.
"This stall was probably caused by a small rock becoming jammed in one of the rover wheel's cleats," said Flight Director David Gruel. "Once the rover detected the stall on its own, she was able to autonomously clear the problem by backing up a short distance. Since the stall did not exist after the backup was performed, there's a high probability that Sojourner is ready to continue the drive around the lander tomorrow."
Approximately 55 megabits of engineering and science data were returned today. All data indicated the lander and rover are healthy and the lander's battery continues to power the craft through the subfreezing nights on Mars. The rover returned a "spectacular" image today of the rear of the lander and the rock nicknamed Mini Matterhorn.
Temperatures on Mars today ranged from a balmy minus 13 degrees Celsius (8 degrees Fahrenheit) at 5:35 p.m. local solar time to minus 79 degrees Celsius (minus 105 degrees Fahrenheit) at 5:30 a.m. local time. Winds were light and from the west.
On this Martian day, Sol 26, Earthrise occurred at 2:09 a.m. PDT and sunrise followed at 5:12 a.m. PDT. The Earth later set at 3:43 p.m. PDT and Pathfinder will observe its 26th sunset at 6 p.m. PDT.
An audio update on Pathfinder's status can be heard by calling 1-800-391-6654.
For more information, please visit our website at http://mpfwww.jpl.nasa.gov.