Driving on Mars is hard on wheels. The image at left shows a pristine wheel of the Perseverance rover, snapped just days after its February 18. The image at right, taken in November 2020, shows one of the wheels of the Curiosity rover, which arrived at Mars in August 2012 and has logged 15 miles (24 km) of driving across the rugged terrain. Engineers designed new wheels for Perseverance to make them stronger and less likely to experience the kind of damage seen on Curiosity. We'll see what they look like in 2029! [NASA/JPL]