Scientists plan to turn astronaut pee and air into edible space food

Scientists, led by the European Space Agency (ESA), are developing a novel method to produce edible protein in space using minimal resources—specifically, microbes from the air and urea derived from astronaut urine. This initiative addresses the critical challenge of sustaining astronauts on long-duration missions, such as trips to Mars, where resupplying food from Earth is impractical due to long transit times. The project, named Hydrogen Oxidizing Bacteria in Weightlessness as a Source of Nutrition (HOBI-WAN), is part of ESA’s Terrae Novae Exploration Programme and focuses on testing a powdered protein called Solein, created by Finnish company Solar Foods. Solein is produced via gas fermentation, where bacteria convert nutrients into an edible powder. On Earth, ammonia serves as the nitrogen source for this process, but in space, urea from urine will replace ammonia due to its availability. Because microgravity affects the behavior of gases and liquids, ESA and its partners, including OHB System AG,