One of the most serious issues of astronauts is zero gravity. This affects their body as it is used to dealing with the gravitational pull of earth. For example, the loss of pressure on bones can destabilize them causing bone loss.
As the Scientific American expertly puts it, “In microgravity, bone loss occurs at a rate of 1 to 1.5 percent a month, leading to an acceleration of age-related changes similar to osteoporosis.Decreases in bone density and strength are more pronounced in some skeletal regions, such as the pelvis, although much of the loss is reversible upon return to Earth.” The effects of space also increases the risk of bone fractures and the body’s ability to heal them.
Muscle loss is another one of the key factors of microgravity. For reasons unknown, microgravity changes the physiology of the heart. When these astronauts return to Earth, some of them may experience an ‘impaired orthostatic response,’ which is when their blood pressure get very low by moving from a lying down position to a sitting position.
These are just two of the many impacts of microgravity. I hope you finished reading this article knowing something new.