Guy Webster 818-354-6278 Mars Exploration Rover Mission Status Report May 18, 2009 Mars and Earth Activities Aim to Get Spirit Rolling Again A diagnostic test on May 16 provided favorable indications about Spirit's left middle wheel. The possibility of the wheel being jammed was one factor in the rover team's May 7 decision to temporarily suspend driving Spirit after that wheel stalled and other wheels had dug themselves about hub-deep into the soil. The test over the weekend showed electrical resistance in the left middle wheel is within the expected range for a motor that has not failed. "This is not a full exoneration of the wheel, but it is encouraging," said John Callas of NASA's Jet Propulsion Laboratory, Another reason to suspend driving is the possibility that the wheels' digging into the soil may have lowered the body of the rover enough for its belly pan to be in contact with a small mound of rocks. The rover team is using NASA's Mars Odyssey orbiter is also aiding in the Spirit recovery plan. As a result of winds blowing dust off Spirit's solar panel four times in the past month, Spirit now has enough power to add an extra communication session each day. The Odyssey project has made the orbiter available for receiving extra transmissions from Spirit. The transmissions include imaging data from Spirit's examinations of soil properties and ground geometry. Rover team members are using that data and other information to construct a simulation of Spirit's situation in a rover testing facility at JPL. The team is testing different materials to use as soil that will mimic the physical properties of the Martian soil where Spirit is embedded. Later, the team will test maneuvers to get the rover free. Weeks of testing are anticipated before any attempt to move Spirit. JPL, a division of the California Institute of Technology in #2009-087 - end - |
