The Boyd group's CVXGEN software has been used in all SpaceX Falcon 9 first stage landings.  

From spacex.com: Falcon 9 is a reusable, two-stage rocket designed and manufactured by SpaceX for the reliable and safe transport of people and payloads into Earth orbit and beyond. Falcon 9 is the world's first orbital class reusable rocket. Reusability allows SpaceX to refly the most expensive parts of the rocket, which in turn drives down the cost of space access.

On December 9, Starship serial number 8 (SN8) lifted off from a Cameron County launch pad and successfully ascended, transitioned propellant, and performed its landing flip maneuver with precise flap control to reach its landing point. Low pressure in the fuel header tank during the landing burn led to high touchdown velocity resulting in a hard (and exciting!) landing. Re-watch SN8's flight here

Although Stephen doesn't plan to travel to Mars, he's thrilled that one day, some of his and his students' work will.