Effect of spaceflight on the human body Effect of spaceflight on the human body Venturing into the environment of space can have negative effects on the human body. Significant adverse effects of long-term weightlessness include muscle atrophy and deterioration of the skeleton (spaceflight osteopenia). Other significant effects include a slowing of cardiovascular system functions, decreased production of red blood cells, balance disorders, eyesight disorders and a weakening of the immune system. Additional symptoms include fluid redistribution (causing the "moon-face" appearance typical in pictures of astronauts experiencing weightlessness), loss of body mass, nasal congestion, sleep disturbance, and excess flatulence. The engineering problems associated with leaving Earth and developing
Effect of spaceflight on the human body changes included a flattening of the eyeball and changes to the retina. Space traveler's eye-sight can become blurry after too much time in space. Another effect is known as Cosmic ray visual phenomena Because weightlessness increases the amount of fluid in the upper part of the body, astronauts experience increased intracranial pressure. This appears to increase pressure on the backs of the eyeballs, affecting their shape and slightly crushing the optic nerve. This effect was noticed in 2012 in a study using MRI scans of astronauts who had returned to Earth following at least one month in space. Such eyesight