Effects Of Living In Space: Among Other Horrors, Space Does Awful Things To Human Eyes

Space does horrible things to human bodies, even when you're ostensibly ensconced inside a habitable metal tube. Zero gravity wastes away the muscles and bones, while the Sun and cosmic rays pound radiation into your cells. Even basic bodily functions (you know which ones I mean, the icky ones) are made so difficult your entire day is basically a relay race between various bags, extraction apparatus and vacuum tubes.

And it turns out, space also does terrifying things to bits of you that would seem to function otherwise normally. Like the eyes.

This frankly disturbing video explains why adult humans suffer such impaired vision after long periods inside the International Space Station. It's fascinating, but also depressing -- just add it to the ever-growing list of reasons why we're almost certainly not going to send a human to Mars until someone finishes off that machine that can print astronauts.