NASA's Mars Exploration Rover Opportunity was sent to Mars four years ago with batteries to last three months. Opportunity and its twin, Spirit, are still operating on Mars.
Wintering on opposite sides of Mars
Opportunity sends this postcard.
Opportunity in Meridiani Planum, near Mars' equator.
Exploring the jagged-edged Victoria Crater.
Opportunity snapped this panorama while p erched on the edge of Duck Bay.
Wind-blown sands form dunes in the center.
The promontory, Cape Verde, and its beautifully detailed rocks.
Sent four years ago with batteries to last three months, Spirit and Opportunity continue captivating the world's imagination.