Imagine a scenario that involves humans leaving the Earth either for good — or for a shorter time on a special mission. It’s sort of like what Matt Damon’s character had to face in the movie The Martian.

To learn more about work being done on how to grow food out of the Earth’s atmosphere, we spoke with Gene Giacomelli. He is director of the Controlled Environment Agriculture Center at the University of Arizona and is heavily involved with the Prototype Lunar Greenhouse project.