Tears Don't Fall in Space: Astronauts Wash With One Cup of Water, and Even Urine Becomes Drinking Water
In microgravity, water doesn't fall. Surface tension pulls it into floating spheres instead, which is why tears never roll down an astronaut's cheeks, they just pool around the eyes. A full-body wash takes about 150-200 mL, one cup, and a recovery system turns 98% of urine, sweat, and even breath moisture back into drinking water. The faucet in your bathroom is not something to take for granted.