The future of space food could be as simple—and weird—as a protein shake made with astronaut breath or a burger made from fungus. For decades, astronauts have relied mostly on pre-packaged food, or the occasional grown lettuce, during their forays off our planet. With missions beyond Earth orbit in sight, a NASA-led competition is hoping to change all that and usher in a new era of sustainable space food.

“Currently the pre-packaged food that we use on the International Space Station has a shelf life of a year and a half,” says Ralph Fritsche, senior project manager for space crop production at NASA’s Kennedy Space Center in Florida. “We don’t have a food system at this point in time that can really handle a mission to Mars,” he says. Longer-duration missions to the moon would present a similar problem.

And while it may be some time before humans ever reach Mars, the moon is very much on the agenda. Next year, NASA plans to send four astronauts flying around the moon as part of its Artemis program, in the first crewed moon mission since Apollo 17 in 1972. The goal is to get humans back on the surface later this decade, at first for days at a time but eventually for weeks, months, or even longer.

To solve the problem of feeding astronauts on long-duration missions, NASA started the Deep Space Food Challenge in January 2021, asking companies to propose novel ways to develop sustainable foods for future missions. About 200 companies entered—a field that was whittled down to 11 teams in January 2023 as part of phase 2, with eight US teams each given $20,000 in funding and three additional international teams also recognized. A handful of winners to be announced in April 2024 following more detailed tests of their proposals. “Phase 2 was kind of a kitchen-level demonstration,” says Angela Herblet at NASA’s Marshall Space Flight Center in Alabama, the project manager for the challenge. “Phase 3 is going to challenge the teams to scale their technologies.”

Entrants had to show systems that could operate for three years and feed a crew of four on a prospective space mission. The proposals did not need to supply a crew’s entire diet, but they did need to create a variety of nutritious foods for the astronauts. Earlier this year, judges then visited each company to “see the food and really analyze it,” says Herblet.

One company took a particularly unusual approach to the task. Air Company, based in New York and one of the eight US-based finalists, designed a system that could use the carbon dioxide expelled by astronauts in space to produce alcohol, which could then be used to grow edible food. The company already develops alcohols from CO2 for plane fuel and perfume.

“It’s making food out of air,” says Stafford Sheehan, cofounder and chief technology officer of Air Company. “It sounds like magic, but when you see it actually operating, it’s much more simple. We’re taking CO2, combining it with water and electricity, and making proteins.”