Object Lessons is a series of short, beautifully designed books about the hidden lives of ordinary things. In 1971, the first lunar rover arrived on the moon. The design became an icon of American ingenuity and the adventurous spirit and vision many equated with the space race. Fifty years later, that vision feels like a nostalgic fantasy, but the lunar rover's legacy paved the way for Mars rovers like Sojourner, Curiosity, and Perseverance. Other rovers have made accessible the world's deepest caves and most remote tundra, extending our exploratory range without risking lives. Still others have been utilized for search and rescue missions or in clean up operations after disasters such as Chernobyl. For all these achievements, rovers embody not just our potential, but our limits. Examining rovers as they wander our terrestrial and celestial boundaries, we might better comprehend our place, and fate, in this universe. Object Lessons is published in partnership with an essay series in _The Atlantic_.