Opportunity:
Opportunity found the strongest evidence yet that liquid water once existed on the surface of Mars. Scientists believe the rover's Meridiani Planum landing site "was once the shoreline of a salty sea on Mars."
Like its sister rover -
Spirit - Opportunity is a full-equipped robot geologist. Both rovers are packed with sensors and cameras that have been revealing Mars in unprecedented detail from microscopic images of rocks to panoramic views of the rocky landscape.
Both rovers are still functioning on Mars. Spirit is exploring the Gusev Crater area on the opposite side of the planet.
Visit the Opportunity Website
