And that's good, because there is a lot of work to do. In Jezero Crater, the rover is studying some of the most ancient rocks in the Solar System, older than any on Earth, dating as far back as about 4 billion years ago. At the time, the planet was in the later stages of the "heavy bombardment" era. "It's the first time we've been able to investigate this terrain in situ, and that's been very exciting," Sun said. Scientists believe the planet might have looked something like the Mojave Desert on Earth, with water flowing through it.

Curiosity is still going strong on Mars after nearly 15 years, and Perseverance operators say the newer rover is doing great as well. For Perseverance, the wheels were redesigned, and there are no signs of appreciable wear and tear, Lee said. The only minor concern is the actuators in the wheels. They were initially life-tested for 20 km of driving, but NASA is in the midst of certifying them to at least 100 km. Perseverance operates on RTG power and has no propellants, consumables, or lubricants on board. For this reason, Lee said, the vehicle could keep driving itself across Mars for many years to come.