Los Angeles ? Spirit, the scientific instrument on wheels that reached the top of a Martian hill this summer after an epic climb, is heading back down toward its next target for exploration.

After two months at the summit of Husband Hill, the six-wheeled rover is descending to a basin where it will examine an outcrop dubbed “home plate” because from orbit it looks like home on a baseball field.

Spirit’s yearlong climb to the peak was a major feat for the Mars rover, which along with its twin, Opportunity, landed on opposite sides of the Red Planet in January 2004.

Spirit has been studying rocks and using its robotic arm to sift the soil to determine how the hill formed. The leading theory is that Husband Hill became uplifted as a result of crater impact.

Mission scientists say a comparison of the summit rocks reveal similar geologic features to those found on the side of the hill. In both cases, the rocks’ makeup reveal they have been altered by water.

It will take about two months for Spirit to make it all the way down Husband Hill.