This week, NASA said goodbye to Opportunity, a rover that roamed the surface of Mars for nearly 15 years before it was silenced by a planet-encompassing dust storm last summer.

Over the years, the rover hit a lot of milestones, including completing a marathon. Its engineers managed to keep it working through standard Mars hazards like brutal temperature swings and dust storms and as it coped with problems of memory loss. In the end, its mission lasted 5,352 Martian days, which is almost 60 times longer than the 90-day mission that it was originally expected to complete.

Data collected by the rover helped show that Mars was once a lot warmer and wetter than it is today. Along the way, it sent 217,000 images back to Earth, giving us a stunning view of our planetary neighbor. Here are a few snapshots from Opportunity’s epic mission.