A Roundup of NASA’s Martian Rovers: A Gallery

Since the late 1990s, NASA has been sending rovers on exploratory missions to Mars. And understandably so—they are far less expensive than manned missions and carry no risk to human life.

There have been five in total: Sojourner, the identical twin rovers Spirit and Opportunity, Curiosity, and, now, Perseverance.

Here’s a look at them all.