After 15 Years, NASA's Mars Rover's Mission is Complete

Opportunity, the longest-lived roving robot, was declared dead by NASA Wednesday.

"It is therefore that I am standing here with a sense of deep appreication and gratitude that I declare the Opportunity mission as complete," said Thomas Zurbuchen, NASA's associate administrator for science.

Opportunity provided an up-close view of Mars for NASA for 15 years. It snapped photos. Opportunity found fine layers of rocks that preserved ripples of flowing water.

Opportunity also changed how NASA explored a planet, instead of just looking into a single spot.

Opportunity lasted much longer than expected. Its twin rover, Spirit, persisted until 2010.

Curiousity, a larger, more capable rover, arrived on Mars in 2012. NASA is planning to launch another rover in 2020.