The rover "Sojourner" is a six-wheeled vehicle launched with the Mars Pathfinder mission. It is controlled by an Earth-based operator, who uses images obtained by both the rover and lander systems. Note that the time delay is about 10 minutes, requiring some autonomous control by the rover. The primary objectives were scheduled for the first seven sols (1 sol = 1 martian day = ~24.7 hours), all within about 10 meters of the lander. The extended mission included more analyses of nearby rock and soil and more tests of the rover capabilities.