From deadly radiation to muscle atrophy, space travel already includes some major challenges when it comes to actually keeping humans alive and healthy. Well, it looks like we could have one more problem to solve before we load up and start exploring the stars.

The first case, involving astronaut John Phillips back in 2005, saw 20/20 eyesight drop to 20/100 in six months — and in the decade since, scientists have charted some form of visual impairment in 80 percent of astronauts. The problem? The backs of Phillips’ eyes had gotten flatter, which pushed his retinas forward, creating something akin to “stretch marks” inflaming his optic nerves. He thought it might get better once he returned to Earth, but the effects didn’t really diminish.

The problem is now officially called visual impairment intracranial pressure syndrome (VIIP), and according to The Washington Post, scientists believe it’s due to the fact that gravity pulls our bodily fluids down. But since that doesn’t happen in space, that extra fluid in the brain increases the pressure in an astronaut’s head. But to fully test that theory would involve drilling into the person’s head or doing a spinal tap.

Scientists and physicians are looking into how to combat the effects, but at this point, they haven’t found anything useful. So, yeah, there’s still work to be done. Here’s hoping we can figure this one out before we master FTL tech.

Zoom In

(Via The Washington Post)