How long has NASA's rover Opportunity been on Mars?
Answer: 12 years
On Jan. 24, NASA celebrated the 12-year anniversary of its Mars rover Opportunity, a machine that was originally intended to last just 90 days. NASA originally predicted that the rover's solar panels would become covered in dust, rendering the machine useless, but Martian dust devils have kept the panels clean, and Opportunity continues to send images to Earth.
