Editor’s note: On Feb. 18, NASA’s Mars 2020 mission arrived at the red planet and successfully landed the Perseverance Rover on the surface. Jim Bell is a professor in the School of Earth and Space Exploration at Arizona State University and has worked on a number of Mars missions. He is the primary investigator leading a team in charge of one of the camera systems on Perseverance. We spoke with him in late January for The Conversation’s new podcast, The Conversation Weekly. Below are excerpts from our conversation that have been edited for length and clarity. What’s the goal of this mission?