It's no secret that staying outside our planet has an extremely negative effect on human health. The muscles of the astronauts atrophy, the skin becomes thinner, the skeleton becomes fragile, and vision deteriorates. And if the muscle mass and hardness of bones are gradually restored upon the return of a person to Earth, then the myopia acquired as a result of such flights can be corrected only by a surgical method.
Thus, the American John Lynch Phillips, who had been on board the International Space Station for over six months, noticed that his visual acuity had dropped from 1 to 0.1 points. And this is far from an isolated example. Scientists have determined that about eighty percent of astronauts experience significant loss of vision. The fault is, perhaps, the lack of gravity and intracranial pressure, as well as cosmic radiation. As you know, closing their eyes in orbit, astronauts do not see blackness, but flashes of light, since cosmic rays constantly bombard the optic nerves.
After examining Phillips, doctors found that the shape of his eyes had changed: the back of the eyeballs were flattened, the retina was pushed forward, folds of the choroid were formed, nerves were inflamed. Apparently, it is weightlessness that leads to such a deformation of the visual organs. In addition, cosmic radiation, which is very harmful even for human skin, stably blinds earthlings in orbit.
Astronauts will return to Earth crippled after flying to Mars
Astronauts' visual impairment is considered one of the main reasons why travel to Mars is seen as very difficult, to say the least. Only a flight there will take about nine months for earthlings, and it will take some more time to do something on the Red Planet, and then fly the same amount back. One can only guess how much the stars will "put" their eyesight for such an expedition, not to mention other health problems. And there is no need to talk about the development of planets outside the solar system.
Experts in the field of biomedicine suggest that the problem can in theory be solved with special head implants that regulate intracranial pressure and blood flow, but their development and testing may take, according to scientists, more than a decade.
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