So astronaut farts have long lives! But astronaut pee is not such a big problem. To get rid of it, astronauts can do a “urine dump.” That’s what they call pumping pee into the freezing blackness of outer space.
Mary Roach writes, “These flash-frozen droplets, illuminated, would look like this silvery snowstorm. I think three different astronauts mentioned how beautiful the urine dump was.”
But if the astronauts were going for a REALLY long trip, they wouldn’t dump their pee. They’d need it for drinking! Recycling and drinking pee already happens on the International Space Station. Just filter the salt and nasty tastes out of the pee and drink it…again and again and again!
Being in outer space exposes people to radiation. So astronauts need radiation shields, and it turns out that food (and poop!) can do that job! Mary Roach says that as a spaceship flies to Mars, astronaut food could line the inside of the space module.
Or as Roach put it, “So you’d fly to Mars in a can of food, and then you’d fly home in a can of poop.”
ADDITION: Astronaut poop has another cool use! Look at this: “First UN Satellite Hopes to Turn Astronaut Poop Into Power Supply”