Nov. 10, 2025, 11:20 a.m. ET Call it pee-cycling. Just in case people thought airline food was inedible: Astronauts on future missions to the Moon and Mars could subsist on a brand new “space food” that is concocted from thin air and urine, the European Space Agency (ESA) announced. “This project aims at developing a key resource which will allow us to improve human spaceflight’s autonomy, resilience and also the well-being of our astronauts,” said Angelique Van Ombergen, the ESA’s chief exploration scientist, the Independent reported. Developed by Finnish startup Solar Foods, Solein, as it’s called, is a highly versatile and fuel-efficient powder that’s manufactured from microbes, air and electricity via a gas fermentation process. “For human beings to be able to implement long-duration missions on the Moon, or even one day, to go to Mars, will require innovative and sustainable solutions to be able to survive with limited supplies,” declared Angelique Van Ombergen, the ESA’s chief exploration scientist. “With this project, the ESA is developing a key capability for the future of space exploration.” Solar Foods Meanwhile, the key ingredient, urea — an organic compound found in urine — provides the essential nitrogen source for synthesizing protein in space. On Earth, this process is facilitated by ammonia. Explore More