Launching anything into space is unbelievably expensive - water costs around $40,000 per litre by the time it reaches orbit. So engineers spent decades inventing a way to recycle every drop on the International Space Station. Today the station reuses about 98% of all the water on board.
The system collects sweat from astronauts’ clothes, moisture from their breath, condensation from the walls, and even urine from the toilet. All of it goes through filters, distillers, and chemical cleaners until it comes out cleaner than most drinking water on Earth. Astronauts joke that “yesterday’s coffee becomes today’s coffee.”
Astronauts have actually said the recycled water tastes better than tap water back home, because it has been so thoroughly filtered. Future missions to the Moon and Mars will have to recycle even more, because resupply missions could be months or years apart. Future space travellers won’t just be drinking their sweat - they’ll be growing food in it, too.
