Rich dude/dreamer Dennis Tito wants to send a man and a woman on a round-trip journey to Mars in 2018. One of the challenges of such a journey: cosmic radiation. A solution for this challenge: lining the walls of the spacecraft with water, food, and — we really hope this stuff isn’t all going to be touching each other — the astronauts’ own feces.

OK, no. The feces isn’t going to touch the food. Here’s how it works:

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The idea is to line the walls of a spacecraft with food and water, which will gradually be replaced by dehydrated waste. (The reclaimed water will be recycled and consumed by the astronauts.) Water, MacCallum explains, serves as a better radiation shield than metal does, because it’s the nuclei of atoms that block the radiation, and water contains more atoms—and therefore more nuclei—per volume than metal does. Food and waste also provide good radiation shielding, and because the food blocks rather than absorbs the radiation, it will remain safe to eat.

Seems like a reasonable idea, and it’s actually one that has been done before. Fine. But here is a question. Why do they always say the trip to Mars is going to be “round-trip”? I mean, like, it fucking better be, right? You’re not going to put these two on a poopship to another planet and then just LEAVE THEM THERE? Also, why does it have to be a man and a woman going to Mars? Is it because that’s “fair”? Or because it’s “romantic”?  Oh well. If we’re going to extend the boundaries of heteronormativity into space, they might as well be encased in poop.

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