08.21.09 - A second, lighter-weight test rover has entered the testing setup at JPL where rover team members are assessing strategy for getting Spirit out of soft soil where it is embedded on Mars.
08.18.09 - Today marks the 2,000th Martian day, or sol, of what was initially planned as a 90-sol mission on Mars for NASA's Spirit rover.
08.13.09 - Mars rover team members are planning a long-duration experiment with the test rover at JPL beginning next week.
08.10.09 - NASA's Mars Rover Opportunity is investigating a metallic meteorite the size of a large watermelon that is providing researchers more details about the Red Planet's environmental history.
08.07.09 - A review on Aug. 6 of test results to date yielded a decision to conduct further checkouts in an augmented testing set-up on Earth.
07.31.09 - The Opportunity rover has eyed an odd-shaped, dark rock, about 0.6 meters (2 feet) across on the surface of Mars, which may be a meteorite.
07.30.09 - Mars rover engineers at JPL are winding down testing of different escape maneuvers using a test rover in a sand box filled with soil to mimic the Martian surface.
07.24.09 - Mars rover team members have begun a new phase of testing at JPL -- using longer-duration experiments -- in their preparations for driving Spirit again on Mars.
07.21.09 - As the Mars rover team uses testing at JPL to evaluate possible ways to drive Spirit out of loose soil on Mars, the team is finishing tests of individual "building block" maneuvers and is about to begin stringing some of those together.
07.21.09 - A live videocast and chat from NASA's Jet Propulsion Laboratory, Pasadena, Calif., will give viewers a chance to ask questions of rover team members working to get Spirit rolling again.
07.16.09 - The Mars rover team is using a test rover at JPL to assess various extraction techniques that might get Spirit out of the loose soil of "Troy" on Mars.
07.14.09 - Scientists have combined a trio of shots taken seconds apart through different colored filters to create a special-effects portrait of a moving dust devil on Mars.
07.13.09 - Engineers checking possible rover movements to get Spirit out of the "Troy" sand trap on Mars are evaluating how a comparable rover at JPL fares in a crablike backward drive, with all four corner wheels turned 60 degrees toward the right.
07.10.09 - On firm ground, NASA's Mars Exploration Rovers can make crablike moves by turning all four steerable wheels to the same side angle, then rotating the wheels either forward or backward.
07.08.09 - Engineers used straight-backward driving of a test rover on Earth on Wednesday, July 8, as they evaluate maneuvers that might be useful for getting Spirit out of a sandtrap on Mars.
07.06.09 - Using a test rover in a sandbox at JPL with special soil simulating Spirit's predicament on Mars, engineers are assessing possible maneuvers for getting Spirit out and onto firmer ground.
07.01.09 - Engineers placed a rock underneath the test rover at NASA's Jet Propulsion Laboratory, Pasadena, Calif., on July 1, 2009, to more closely simulate Spirit's predicament on Mars.
06.30.09 - After several days of preparing a sloped area of soft, fine soil to simulate Spirit's current sandtrap on Mars, the rover team drove a test rover into the material on June 30, 2009.
06.25.09 - NASA's Mars rover Spirit, lodged in Martian soil that is causing traction trouble, is taking advantage of the situation by learning more about the Red Planet's environmental history.
05.26.09 - In a giant leap for Roverkind, NASA's Mars Exploration Rover Opportunity's odometer clocked past the 10-mile mark (16,133.96 meters) on May 25 (Sol 1897).