Spirit Mars Rover Reaches Hills, Opportunity Goes Deep

The Spirit and Opportunity rovers have each entered a new stage of exploration on Mars. For Spirit, the robot has pulled up at the base of the Columbia Hills, following a record-setting trek across the landscape of Gusev Crater. Meanwhile, on the other side of the planet at Meridiani Planum, the Opportunity rover is studying science-rich targets within the sloping walls of the large impact crater dubbed Endurance.