Scientists in Japan have developed a portable device that turns air into fertilizer and have successfully used it to grow rice seedlings in soil designed to mimic the Moon’s surface. Turning air into plant foodOne of the biggest challenges of growing crops on the Moon is the lack of fertile soil. Regolith, or the Moon’s soil, contains no organic material, and essential plant nitrogen sources like ammonia and nitrate are virtually nonexistent. Helping rice thrive in lunar soilKaneko and his colleagues tested whether the N₂O₅-dissolved water could serve as a local nitrogen fertilizer to grow rice seedlings within a lunar regolith simulant. The nitrate-rich water reduced the lunar regolith simulant’s alkalinity, lowering its pH from 9.09 to a plant-friendly 6.76.