As an expert in space exploration and the technology used by astronauts, I can provide you with a detailed answer about what they drink in space. Astronauts aboard the International Space Station (ISS) have access to a variety of beverages, but the primary source of their drinking water is recycled. This is achieved through a sophisticated water recovery system that turns waste, including urine, into drinkable water. The ISS is managed by different countries, and as you mentioned, there are two distinct water systems: one operated by Russia and the other by the United States. The U.S. water system is particularly advanced and is capable of collecting condensate from the environment, water that has been used (runoff), and urine. Through a process of filtration and purification, it can convert these sources into approximately 3.6 gallons of drinkable water each day. This system is a testament to the ingenuity required to sustain life in the challenging environment of space. While some astronauts may not drink recycled urine, it is important to note that all water on the ISS, regardless of its original source, is subjected to the same rigorous purification process. This ensures that the water is safe to drink and meets or exceeds the quality standards set by航天局 (space agencies). read more >>

However, not all the ISS astronauts drink recycled urine. The ISS is split into two sections, one run by Russia, and one by the United States, and they have two different water systems. The U.S. system collects condensate, runoff, and urine to create about 3.6 gallons of drinkable water per day.read more >>